Public Types | Public Member Functions | Static Public Member Functions | Protected Member Functions | Related Functions
DenseBase< Derived > Class Template Reference

Base class for all dense matrices, vectors, and arrays. More...

+ Inheritance diagram for DenseBase< Derived >:

List of all members.

Public Types

enum  {
  RowsAtCompileTime,
  ColsAtCompileTime,
  SizeAtCompileTime,
  MaxRowsAtCompileTime,
  MaxColsAtCompileTime,
  MaxSizeAtCompileTime,
  IsVectorAtCompileTime,
  Flags,
  IsRowMajor ,
  CoeffReadCost
}
typedef internal::traits
< Derived >::Index 
Index
 The type of indices.

Public Member Functions

bool all (void) const
bool any (void) const
Block< Derived > block (Index startRow, Index startCol, Index blockRows, Index blockCols)
const Block< const Derived > block (Index startRow, Index startCol, Index blockRows, Index blockCols) const
template<int BlockRows, int BlockCols>
Block< Derived, BlockRows,
BlockCols > 
block (Index startRow, Index startCol)
template<int BlockRows, int BlockCols>
const Block< const Derived,
BlockRows, BlockCols > 
block (Index startRow, Index startCol) const
Block< Derived > bottomLeftCorner (Index cRows, Index cCols)
const Block< const Derived > bottomLeftCorner (Index cRows, Index cCols) const
template<int CRows, int CCols>
Block< Derived, CRows, CCols > bottomLeftCorner ()
template<int CRows, int CCols>
const Block< const Derived,
CRows, CCols > 
bottomLeftCorner () const
Block< Derived > bottomRightCorner (Index cRows, Index cCols)
const Block< const Derived > bottomRightCorner (Index cRows, Index cCols) const
template<int CRows, int CCols>
Block< Derived, CRows, CCols > bottomRightCorner ()
template<int CRows, int CCols>
const Block< const Derived,
CRows, CCols > 
bottomRightCorner () const
RowsBlockXpr bottomRows (Index n)
ConstRowsBlockXpr bottomRows (Index n) const
template<int N>
NRowsBlockXpr< N >::Type bottomRows ()
template<int N>
ConstNRowsBlockXpr< N >::Type bottomRows () const
ColXpr col (Index i)
ConstColXpr col (Index i) const
ConstColwiseReturnType colwise () const
ColwiseReturnType colwise ()
Index count () const
const internal::eval< Derived >
::type 
eval () const
void fill (const Scalar &value)
template<unsigned int Added, unsigned int Removed>
const Flagged< Derived, Added,
Removed > 
flagged () const
const WithFormat< Derived > format (const IOFormat &fmt) const
SegmentReturnType head (Index size)
DenseBase::ConstSegmentReturnType head (Index size) const
template<int Size>
FixedSegmentReturnType< Size >
::Type 
head ()
template<int Size>
ConstFixedSegmentReturnType
< Size >::Type 
head () const
Index innerSize () const
template<typename OtherDerived >
bool isApprox (const DenseBase< OtherDerived > &other, RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
bool isApproxToConstant (const Scalar &value, RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
bool isConstant (const Scalar &value, RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
template<typename Derived >
bool isMuchSmallerThan (const typename NumTraits< Scalar >::Real &other, RealScalar prec) const
template<typename OtherDerived >
bool isMuchSmallerThan (const DenseBase< OtherDerived > &other, RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
bool isOnes (RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
bool isZero (RealScalar prec=NumTraits< Scalar >::dummy_precision()) const
ColsBlockXpr leftCols (Index n)
ConstColsBlockXpr leftCols (Index n) const
template<int N>
NColsBlockXpr< N >::Type leftCols ()
template<int N>
ConstNColsBlockXpr< N >::Type leftCols () const
internal::traits< Derived >::Scalar maxCoeff () const
template<typename IndexType >
internal::traits< Derived >::Scalar maxCoeff (IndexType *row, IndexType *col) const
template<typename IndexType >
internal::traits< Derived >::Scalar maxCoeff (IndexType *index) const
Scalar mean () const
ColsBlockXpr middleCols (Index startCol, Index numCols)
ConstColsBlockXpr middleCols (Index startCol, Index numCols) const
template<int N>
NColsBlockXpr< N >::Type middleCols (Index startCol)
template<int N>
ConstNColsBlockXpr< N >::Type middleCols (Index startCol) const
RowsBlockXpr middleRows (Index startRow, Index numRows)
ConstRowsBlockXpr middleRows (Index startRow, Index numRows) const
template<int N>
NRowsBlockXpr< N >::Type middleRows (Index startRow)
template<int N>
ConstNRowsBlockXpr< N >::Type middleRows (Index startRow) const
internal::traits< Derived >::Scalar minCoeff () const
template<typename IndexType >
internal::traits< Derived >::Scalar minCoeff (IndexType *row, IndexType *col) const
template<typename IndexType >
internal::traits< Derived >::Scalar minCoeff (IndexType *index) const
const NestByValue< Derived > nestByValue () const
Index nonZeros () const
CommaInitializer< Derived > operator<< (const Scalar &s)
template<typename OtherDerived >
CommaInitializer< Derived > operator<< (const DenseBase< OtherDerived > &other)
template<typename OtherDerived >
Derived & operator= (const DenseBase< OtherDerived > &other)
Derived & operator= (const DenseBase &other)
template<typename OtherDerived >
Derived & operator= (const EigenBase< OtherDerived > &other)
 Copies the generic expression other into *this.
Index outerSize () const
Scalar prod () const
template<int RowFactor, int ColFactor>
const Replicate< Derived,
RowFactor, ColFactor > 
replicate () const
const Replicate< Derived,
Dynamic, Dynamic
replicate (Index rowFacor, Index colFactor) const
void resize (Index size)
void resize (Index rows, Index cols)
ReverseReturnType reverse ()
ConstReverseReturnType reverse () const
void reverseInPlace ()
ColsBlockXpr rightCols (Index n)
ConstColsBlockXpr rightCols (Index n) const
template<int N>
NColsBlockXpr< N >::Type rightCols ()
template<int N>
ConstNColsBlockXpr< N >::Type rightCols () const
RowXpr row (Index i)
ConstRowXpr row (Index i) const
ConstRowwiseReturnType rowwise () const
RowwiseReturnType rowwise ()
SegmentReturnType segment (Index start, Index size)
DenseBase::ConstSegmentReturnType segment (Index start, Index size) const
template<int Size>
FixedSegmentReturnType< Size >
::Type 
segment (Index start)
template<int Size>
ConstFixedSegmentReturnType
< Size >::Type 
segment (Index start) const
template<typename ThenDerived , typename ElseDerived >
const Select< Derived,
ThenDerived, ElseDerived > 
select (const DenseBase< ThenDerived > &thenMatrix, const DenseBase< ElseDerived > &elseMatrix) const
template<typename ThenDerived >
const Select< Derived,
ThenDerived, typename
ThenDerived::ConstantReturnType > 
select (const DenseBase< ThenDerived > &thenMatrix, typename ThenDerived::Scalar elseScalar) const
template<typename ElseDerived >
const Select< Derived,
typename
ElseDerived::ConstantReturnType,
ElseDerived > 
select (typename ElseDerived::Scalar thenScalar, const DenseBase< ElseDerived > &elseMatrix) const
Derived & setConstant (const Scalar &value)
Derived & setLinSpaced (Index size, const Scalar &low, const Scalar &high)
 Sets a linearly space vector.
Derived & setOnes ()
Derived & setRandom ()
Derived & setZero ()
Scalar sum () const
template<typename OtherDerived >
void swap (const DenseBase< OtherDerived > &other, int=OtherDerived::ThisConstantIsPrivateInPlainObjectBase)
template<typename OtherDerived >
void swap (PlainObjectBase< OtherDerived > &other)
SegmentReturnType tail (Index size)
DenseBase::ConstSegmentReturnType tail (Index size) const
template<int Size>
FixedSegmentReturnType< Size >
::Type 
tail ()
template<int Size>
ConstFixedSegmentReturnType
< Size >::Type 
tail () const
Block< Derived > topLeftCorner (Index cRows, Index cCols)
const Block< const Derived > topLeftCorner (Index cRows, Index cCols) const
template<int CRows, int CCols>
Block< Derived, CRows, CCols > topLeftCorner ()
template<int CRows, int CCols>
const Block< const Derived,
CRows, CCols > 
topLeftCorner () const
Block< Derived > topRightCorner (Index cRows, Index cCols)
const Block< const Derived > topRightCorner (Index cRows, Index cCols) const
template<int CRows, int CCols>
Block< Derived, CRows, CCols > topRightCorner ()
template<int CRows, int CCols>
const Block< const Derived,
CRows, CCols > 
topRightCorner () const
RowsBlockXpr topRows (Index n)
ConstRowsBlockXpr topRows (Index n) const
template<int N>
NRowsBlockXpr< N >::Type topRows ()
template<int N>
ConstNRowsBlockXpr< N >::Type topRows () const
Eigen::Transpose< Derived > transpose ()
ConstTransposeReturnType transpose () const
void transposeInPlace ()
CoeffReturnType value () const
template<typename Visitor >
void visit (Visitor &func) const

Static Public Member Functions

static const ConstantReturnType Constant (Index rows, Index cols, const Scalar &value)
static const ConstantReturnType Constant (Index size, const Scalar &value)
static const ConstantReturnType Constant (const Scalar &value)
static const
SequentialLinSpacedReturnType 
LinSpaced (Sequential_t, Index size, const Scalar &low, const Scalar &high)
 Sets a linearly space vector.
static const
RandomAccessLinSpacedReturnType 
LinSpaced (Index size, const Scalar &low, const Scalar &high)
 Sets a linearly space vector.
static const
SequentialLinSpacedReturnType 
LinSpaced (Sequential_t, const Scalar &low, const Scalar &high)
 Sets a linearly space vector.
static const
RandomAccessLinSpacedReturnType 
LinSpaced (const Scalar &low, const Scalar &high)
 Sets a linearly space vector.
template<typename CustomNullaryOp >
static const CwiseNullaryOp
< CustomNullaryOp, Derived > 
NullaryExpr (Index rows, Index cols, const CustomNullaryOp &func)
template<typename CustomNullaryOp >
static const CwiseNullaryOp
< CustomNullaryOp, Derived > 
NullaryExpr (Index size, const CustomNullaryOp &func)
template<typename CustomNullaryOp >
static const CwiseNullaryOp
< CustomNullaryOp, Derived > 
NullaryExpr (const CustomNullaryOp &func)
static const ConstantReturnType Ones (Index rows, Index cols)
static const ConstantReturnType Ones (Index size)
static const ConstantReturnType Ones ()
static const CwiseNullaryOp
< internal::scalar_random_op
< Scalar >, Derived > 
Random (Index rows, Index cols)
static const CwiseNullaryOp
< internal::scalar_random_op
< Scalar >, Derived > 
Random (Index size)
static const CwiseNullaryOp
< internal::scalar_random_op
< Scalar >, Derived > 
Random ()
static const ConstantReturnType Zero (Index rows, Index cols)
static const ConstantReturnType Zero (Index size)
static const ConstantReturnType Zero ()

Protected Member Functions

 DenseBase ()

Related Functions

(Note that these are not member functions.)

template<typename Derived >
std::ostream & operator<< (std::ostream &s, const DenseBase< Derived > &m)

Detailed Description

template<typename Derived>
class Eigen::DenseBase< Derived >

Base class for all dense matrices, vectors, and arrays.

This class is the base that is inherited by all dense objects (matrix, vector, arrays, and related expression types). The common Eigen API for dense objects is contained in this class.

Template Parameters:
Derivedis the derived type, e.g., a matrix type or an expression.

This class can be extended with the help of the plugin mechanism described on the page Customizing/Extending Eigen by defining the preprocessor symbol EIGEN_DENSEBASE_PLUGIN.

See also:
The class hierarchy

Member Typedef Documentation

typedef internal::traits<Derived>::Index Index

The type of indices.

To change this, #define the preprocessor symbol EIGEN_DEFAULT_DENSE_INDEX_TYPE.

See also:
Preprocessor directives.

Member Enumeration Documentation

anonymous enum
Enumerator:
RowsAtCompileTime 

The number of rows at compile-time. This is just a copy of the value provided by the Derived type. If a value is not known at compile-time, it is set to the Dynamic constant.

See also:
MatrixBase::rows(), MatrixBase::cols(), ColsAtCompileTime, SizeAtCompileTime
ColsAtCompileTime 

The number of columns at compile-time. This is just a copy of the value provided by the Derived type. If a value is not known at compile-time, it is set to the Dynamic constant.

See also:
MatrixBase::rows(), MatrixBase::cols(), RowsAtCompileTime, SizeAtCompileTime
SizeAtCompileTime 

This is equal to the number of coefficients, i.e. the number of rows times the number of columns, or to Dynamic if this is not known at compile-time.

See also:
RowsAtCompileTime, ColsAtCompileTime
MaxRowsAtCompileTime 

This value is equal to the maximum possible number of rows that this expression might have. If this expression might have an arbitrarily high number of rows, this value is set to Dynamic.

This value is useful to know when evaluating an expression, in order to determine whether it is possible to avoid doing a dynamic memory allocation.

See also:
RowsAtCompileTime, MaxColsAtCompileTime, MaxSizeAtCompileTime
MaxColsAtCompileTime 

This value is equal to the maximum possible number of columns that this expression might have. If this expression might have an arbitrarily high number of columns, this value is set to Dynamic.

This value is useful to know when evaluating an expression, in order to determine whether it is possible to avoid doing a dynamic memory allocation.

See also:
ColsAtCompileTime, MaxRowsAtCompileTime, MaxSizeAtCompileTime
MaxSizeAtCompileTime 

This value is equal to the maximum possible number of coefficients that this expression might have. If this expression might have an arbitrarily high number of coefficients, this value is set to Dynamic.

This value is useful to know when evaluating an expression, in order to determine whether it is possible to avoid doing a dynamic memory allocation.

See also:
SizeAtCompileTime, MaxRowsAtCompileTime, MaxColsAtCompileTime
IsVectorAtCompileTime 

This is set to true if either the number of rows or the number of columns is known at compile-time to be equal to 1. Indeed, in that case, we are dealing with a column-vector (if there is only one column) or with a row-vector (if there is only one row).

Flags 

This stores expression Flags flags which may or may not be inherited by new expressions constructed from this one. See the list of flags.

IsRowMajor 

True if this expression has row-major storage order.

CoeffReadCost 

This is a rough measure of how expensive it is to read one coefficient from this expression.


Constructor & Destructor Documentation

DenseBase ( ) [inline, protected]

Default constructor. Do nothing.


Member Function Documentation

bool all ( void  ) const [inline]
Returns:
true if all coefficients are true

Example:

Vector3f boxMin(Vector3f::Zero()), boxMax(Vector3f::Ones());
Vector3f p0 = Vector3f::Random(), p1 = Vector3f::Random().cwiseAbs();
// let's check if p0 and p1 are inside the axis aligned box defined by the corners boxMin,boxMax:
cout << "Is (" << p0.transpose() << ") inside the box: "
     << ((boxMin.array()<p0.array()).all() && (boxMax.array()>p0.array()).all()) << endl;
cout << "Is (" << p1.transpose() << ") inside the box: "
     << ((boxMin.array()<p1.array()).all() && (boxMax.array()>p1.array()).all()) << endl;

Output:

Is (  0.68 -0.211  0.566) inside the box: 0
Is (0.597 0.823 0.605) inside the box: 1
See also:
any(), Cwise::operator<()
bool any ( void  ) const [inline]
Returns:
true if at least one coefficient is true
See also:
all()
Block<Derived> block ( Index  startRow,
Index  startCol,
Index  blockRows,
Index  blockCols 
) [inline]
Returns:
a dynamic-size expression of a block in *this.
Parameters:
startRowthe first row in the block
startColthe first column in the block
blockRowsthe number of rows in the block
blockColsthe number of columns in the block

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.block(1, 1, 2, 2):" << endl << m.block(1, 1, 2, 2) << endl;
m.block(1, 1, 2, 2).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.block(1, 1, 2, 2):
-6 1
-3 0
Now the matrix m is:
 7  9 -5 -3
-2  0  0  0
 6  0  0  9
 6  6  3  9
Note:
Even though the returned expression has dynamic size, in the case when it is applied to a fixed-size matrix, it inherits a fixed maximal size, which means that evaluating it does not cause a dynamic memory allocation.
See also:
class Block, block(Index,Index)
const Block<const Derived> block ( Index  startRow,
Index  startCol,
Index  blockRows,
Index  blockCols 
) const [inline]

This is the const version of block(Index,Index,Index,Index).

Block<Derived, BlockRows, BlockCols> block ( Index  startRow,
Index  startCol 
) [inline]
Returns:
a fixed-size expression of a block in *this.

The template parameters BlockRows and BlockCols are the number of rows and columns in the block.

Parameters:
startRowthe first row in the block
startColthe first column in the block

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.block<2,2>(1,1):" << endl << m.block<2,2>(1,1) << endl;
m.block<2,2>(1,1).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.block<2,2>(1,1):
-6 1
-3 0
Now the matrix m is:
 7  9 -5 -3
-2  0  0  0
 6  0  0  9
 6  6  3  9
Note:
since block is a templated member, the keyword template has to be used if the matrix type is also a template parameter:
 m.template block<3,3>(1,1); 
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived, BlockRows, BlockCols> block ( Index  startRow,
Index  startCol 
) const [inline]

This is the const version of block<>(Index, Index).

Block<Derived> bottomLeftCorner ( Index  cRows,
Index  cCols 
) [inline]
Returns:
a dynamic-size expression of a bottom-left corner of *this.
Parameters:
cRowsthe number of rows in the corner
cColsthe number of columns in the corner

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.bottomLeftCorner(2, 2):" << endl;
cout << m.bottomLeftCorner(2, 2) << endl;
m.bottomLeftCorner(2, 2).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.bottomLeftCorner(2, 2):
 6 -3
 6  6
Now the matrix m is:
 7  9 -5 -3
-2 -6  1  0
 0  0  0  9
 0  0  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived> bottomLeftCorner ( Index  cRows,
Index  cCols 
) const [inline]

This is the const version of bottomLeftCorner(Index, Index).

Block<Derived, CRows, CCols> bottomLeftCorner ( ) [inline]
Returns:
an expression of a fixed-size bottom-left corner of *this.

The template parameters CRows and CCols are the number of rows and columns in the corner.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.bottomLeftCorner<2,2>():" << endl;
cout << m.bottomLeftCorner<2,2>() << endl;
m.bottomLeftCorner<2,2>().setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.bottomLeftCorner<2,2>():
 6 -3
 6  6
Now the matrix m is:
 7  9 -5 -3
-2 -6  1  0
 0  0  0  9
 0  0  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived, CRows, CCols> bottomLeftCorner ( ) const [inline]

This is the const version of bottomLeftCorner<int, int>().

Block<Derived> bottomRightCorner ( Index  cRows,
Index  cCols 
) [inline]
Returns:
a dynamic-size expression of a bottom-right corner of *this.
Parameters:
cRowsthe number of rows in the corner
cColsthe number of columns in the corner

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.bottomRightCorner(2, 2):" << endl;
cout << m.bottomRightCorner(2, 2) << endl;
m.bottomRightCorner(2, 2).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.bottomRightCorner(2, 2):
0 9
3 9
Now the matrix m is:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  0
 6  6  0  0
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived> bottomRightCorner ( Index  cRows,
Index  cCols 
) const [inline]

This is the const version of bottomRightCorner(Index, Index).

Block<Derived, CRows, CCols> bottomRightCorner ( ) [inline]
Returns:
an expression of a fixed-size bottom-right corner of *this.

The template parameters CRows and CCols are the number of rows and columns in the corner.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.bottomRightCorner<2,2>():" << endl;
cout << m.bottomRightCorner<2,2>() << endl;
m.bottomRightCorner<2,2>().setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.bottomRightCorner<2,2>():
0 9
3 9
Now the matrix m is:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  0
 6  6  0  0
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived, CRows, CCols> bottomRightCorner ( ) const [inline]

This is the const version of bottomRightCorner<int, int>().

RowsBlockXpr bottomRows ( Index  n) [inline]
Returns:
a block consisting of the bottom rows of *this.
Parameters:
nthe number of rows in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.bottomRows(2):" << endl;
cout << a.bottomRows(2) << endl;
a.bottomRows(2).setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.bottomRows(2):
 6 -3  0  9
 6  6  3  9
Now the array a is:
 7  9 -5 -3
-2 -6  1  0
 0  0  0  0
 0  0  0  0
See also:
class Block, block(Index,Index,Index,Index)
ConstRowsBlockXpr bottomRows ( Index  n) const [inline]

This is the const version of bottomRows(Index).

NRowsBlockXpr<N>::Type bottomRows ( ) [inline]
Returns:
a block consisting of the bottom rows of *this.
Template Parameters:
Nthe number of rows in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.bottomRows<2>():" << endl;
cout << a.bottomRows<2>() << endl;
a.bottomRows<2>().setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.bottomRows<2>():
 6 -3  0  9
 6  6  3  9
Now the array a is:
 7  9 -5 -3
-2 -6  1  0
 0  0  0  0
 0  0  0  0
See also:
class Block, block(Index,Index,Index,Index)
ConstNRowsBlockXpr<N>::Type bottomRows ( ) const [inline]

This is the const version of bottomRows<int>().

ColXpr col ( Index  i) [inline]
Returns:
an expression of the i-th column of *this. Note that the numbering starts at 0.

Example:

Matrix3d m = Matrix3d::Identity();
m.col(1) = Vector3d(4,5,6);
cout << m << endl;

Output:

1 4 0
0 5 0
0 6 1
See also:
row(), class Block
ConstColXpr col ( Index  i) const [inline]

This is the const version of col().

const DenseBase< Derived >::ConstColwiseReturnType colwise ( ) const [inline]
Returns:
a VectorwiseOp wrapper of *this providing additional partial reduction operations

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the sum of each column:" << endl << m.colwise().sum() << endl;
cout << "Here is the maximum absolute value of each column:"
     << endl << m.cwiseAbs().colwise().maxCoeff() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the sum of each column:
  1.04  0.815 -0.238
Here is the maximum absolute value of each column:
 0.68 0.823 0.536
See also:
rowwise(), class VectorwiseOp
DenseBase< Derived >::ColwiseReturnType colwise ( ) [inline]
Returns:
a writable VectorwiseOp wrapper of *this providing additional partial reduction operations
See also:
rowwise(), class VectorwiseOp
const DenseBase< Derived >::ConstantReturnType Constant ( Index  rows,
Index  cols,
const Scalar &  value 
) [inline, static]
Returns:
an expression of a constant matrix of value value

The parameters rows and cols are the number of rows and of columns of the returned matrix. Must be compatible with this DenseBase type.

This variant is meant to be used for dynamic-size matrix types. For fixed-size types, it is redundant to pass rows and cols as arguments, so Zero() should be used instead.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
const DenseBase< Derived >::ConstantReturnType Constant ( Index  size,
const Scalar &  value 
) [inline, static]
Returns:
an expression of a constant matrix of value value

The parameter size is the size of the returned vector. Must be compatible with this DenseBase type.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

This variant is meant to be used for dynamic-size vector types. For fixed-size types, it is redundant to pass size as argument, so Zero() should be used instead.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
const DenseBase< Derived >::ConstantReturnType Constant ( const Scalar &  value) [inline, static]
Returns:
an expression of a constant matrix of value value

This variant is only for fixed-size DenseBase types. For dynamic-size types, you need to use the variants taking size arguments.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
DenseBase< Derived >::Index count ( ) const [inline]
Returns:
the number of coefficients which evaluate to true
See also:
all(), any()
const internal::eval<Derived>::type eval ( ) const [inline]
Returns:
the matrix or vector obtained by evaluating this expression.

Notice that in the case of a plain matrix or vector (not an expression) this function just returns a const reference, in order to avoid a useless copy.

void fill ( const Scalar &  value) [inline]

Alias for setConstant(): sets all coefficients in this expression to value.

See also:
setConstant(), Constant(), class CwiseNullaryOp
const Flagged< Derived, Added, Removed > flagged ( ) const [inline]
Returns:
an expression of *this with added and removed flags

This is mostly for internal use.

See also:
class Flagged
const WithFormat< Derived > format ( const IOFormat fmt) const [inline]
Returns:
a WithFormat proxy object allowing to print a matrix the with given format fmt.

See class IOFormat for some examples.

See also:
class IOFormat, class WithFormat
DenseBase< Derived >::SegmentReturnType head ( Index  size) [inline]
Returns:
a dynamic-size expression of the first coefficients of *this.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Parameters:
sizethe number of coefficients in the block

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.head(2):" << endl << v.head(2) << endl;
v.head(2).setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.head(2):
 7 -2
Now the vector v is:
0 0 6 6
Note:
Even though the returned expression has dynamic size, in the case when it is applied to a fixed-size vector, it inherits a fixed maximal size, which means that evaluating it does not cause a dynamic memory allocation.
See also:
class Block, block(Index,Index)
DenseBase< Derived >::ConstSegmentReturnType head ( Index  size) const [inline]

This is the const version of head(Index).

DenseBase< Derived >::template FixedSegmentReturnType< Size >::Type head ( ) [inline]
Returns:
a fixed-size expression of the first coefficients of *this.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

The template parameter Size is the number of coefficients in the block

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.head(2):" << endl << v.head<2>() << endl;
v.head<2>().setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.head(2):
 7 -2
Now the vector v is:
0 0 6 6
See also:
class Block
DenseBase< Derived >::template ConstFixedSegmentReturnType< Size >::Type head ( ) const [inline]

This is the const version of head<int>().

Index innerSize ( ) const [inline]
Returns:
the inner size.
Note:
For a vector, this is just the size. For a matrix (non-vector), this is the minor dimension with respect to the storage order, i.e., the number of rows for a column-major matrix, and the number of columns for a row-major matrix.
bool isApprox ( const DenseBase< OtherDerived > &  other,
RealScalar  prec = NumTraits<Scalar>::dummy_precision() 
) const
Returns:
true if *this is approximately equal to other, within the precision determined by prec.
Note:
The fuzzy compares are done multiplicatively. Two vectors $ v $ and $ w $ are considered to be approximately equal within precision $ p $ if

\[ \Vert v - w \Vert \leqslant p\,\min(\Vert v\Vert, \Vert w\Vert). \]

For matrices, the comparison is done using the Hilbert-Schmidt norm (aka Frobenius norm L2 norm).
Because of the multiplicativeness of this comparison, one can't use this function to check whether *this is approximately equal to the zero matrix or vector. Indeed, isApprox(zero) returns false unless *this itself is exactly the zero matrix or vector. If you want to test whether *this is zero, use internal::isMuchSmallerThan(const RealScalar&, RealScalar) instead.
See also:
internal::isMuchSmallerThan(const RealScalar&, RealScalar) const
bool isApproxToConstant ( const Scalar &  value,
RealScalar  prec = NumTraits<Scalar>::dummy_precision() 
) const
Returns:
true if all coefficients in this matrix are approximately equal to value, to within precision prec
bool isConstant ( const Scalar &  value,
RealScalar  prec = NumTraits<Scalar>::dummy_precision() 
) const

This is just an alias for isApproxToConstant().

Returns:
true if all coefficients in this matrix are approximately equal to value, to within precision prec
bool isMuchSmallerThan ( const typename NumTraits< Scalar >::Real &  other,
RealScalar  prec 
) const
Returns:
true if the norm of *this is much smaller than other, within the precision determined by prec.
Note:
The fuzzy compares are done multiplicatively. A vector $ v $ is considered to be much smaller than $ x $ within precision $ p $ if

\[ \Vert v \Vert \leqslant p\,\vert x\vert. \]

For matrices, the comparison is done using the Hilbert-Schmidt norm. For this reason, the value of the reference scalar other should come from the Hilbert-Schmidt norm of a reference matrix of same dimensions.

See also:
isApprox(), isMuchSmallerThan(const DenseBase<OtherDerived>&, RealScalar) const
bool isMuchSmallerThan ( const DenseBase< OtherDerived > &  other,
RealScalar  prec = NumTraits<Scalar>::dummy_precision() 
) const
Returns:
true if the norm of *this is much smaller than the norm of other, within the precision determined by prec.
Note:
The fuzzy compares are done multiplicatively. A vector $ v $ is considered to be much smaller than a vector $ w $ within precision $ p $ if

\[ \Vert v \Vert \leqslant p\,\Vert w\Vert. \]

For matrices, the comparison is done using the Hilbert-Schmidt norm.
See also:
isApprox(), isMuchSmallerThan(const RealScalar&, RealScalar) const
bool isOnes ( RealScalar  prec = NumTraits<Scalar>::dummy_precision()) const
Returns:
true if *this is approximately equal to the matrix where all coefficients are equal to 1, within the precision given by prec.

Example:

Matrix3d m = Matrix3d::Ones();
m(0,2) += 1e-4;
cout << "Here's the matrix m:" << endl << m << endl;
cout << "m.isOnes() returns: " << m.isOnes() << endl;
cout << "m.isOnes(1e-3) returns: " << m.isOnes(1e-3) << endl;

Output:

Here's the matrix m:
1 1 1
1 1 1
1 1 1
m.isOnes() returns: 0
m.isOnes(1e-3) returns: 1
See also:
class CwiseNullaryOp, Ones()
bool isZero ( RealScalar  prec = NumTraits<Scalar>::dummy_precision()) const
Returns:
true if *this is approximately equal to the zero matrix, within the precision given by prec.

Example:

Matrix3d m = Matrix3d::Zero();
m(0,2) = 1e-4;
cout << "Here's the matrix m:" << endl << m << endl;
cout << "m.isZero() returns: " << m.isZero() << endl;
cout << "m.isZero(1e-3) returns: " << m.isZero(1e-3) << endl;

Output:

Here's the matrix m:
     0      0 0.0001
     0      0      0
     0      0      0
m.isZero() returns: 0
m.isZero(1e-3) returns: 1
See also:
class CwiseNullaryOp, Zero()
ColsBlockXpr leftCols ( Index  n) [inline]
Returns:
a block consisting of the left columns of *this.
Parameters:
nthe number of columns in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.leftCols(2):" << endl;
cout << a.leftCols(2) << endl;
a.leftCols(2).setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.leftCols(2):
 7  9
-2 -6
 6 -3
 6  6
Now the array a is:
 0  0 -5 -3
 0  0  1  0
 0  0  0  9
 0  0  3  9
See also:
class Block, block(Index,Index,Index,Index)
ConstColsBlockXpr leftCols ( Index  n) const [inline]

This is the const version of leftCols(Index).

NColsBlockXpr<N>::Type leftCols ( ) [inline]
Returns:
a block consisting of the left columns of *this.
Template Parameters:
Nthe number of columns in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.leftCols<2>():" << endl;
cout << a.leftCols<2>() << endl;
a.leftCols<2>().setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.leftCols<2>():
 7  9
-2 -6
 6 -3
 6  6
Now the array a is:
 0  0 -5 -3
 0  0  1  0
 0  0  0  9
 0  0  3  9
See also:
class Block, block(Index,Index,Index,Index)
ConstNColsBlockXpr<N>::Type leftCols ( ) const [inline]

This is the const version of leftCols<int>().

const DenseBase< Derived >::SequentialLinSpacedReturnType LinSpaced ( Sequential_t  ,
Index  size,
const Scalar &  low,
const Scalar &  high 
) [inline, static]

Sets a linearly space vector.

The function generates 'size' equally spaced values in the closed interval [low,high]. This particular version of LinSpaced() uses sequential access, i.e. vector access is assumed to be a(0), a(1), ..., a(size). This assumption allows for better vectorization and yields faster code than the random access version.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Example:

cout << VectorXi::LinSpaced(Sequential,4,7,10).transpose() << endl;
cout << VectorXd::LinSpaced(Sequential,5,0.0,1.0).transpose() << endl;

Output:

 7  8  9 10
   0 0.25  0.5 0.75    1
See also:
setLinSpaced(Index,const Scalar&,const Scalar&), LinSpaced(Index,Scalar,Scalar), CwiseNullaryOp
const DenseBase< Derived >::RandomAccessLinSpacedReturnType LinSpaced ( Index  size,
const Scalar &  low,
const Scalar &  high 
) [inline, static]

Sets a linearly space vector.

The function generates 'size' equally spaced values in the closed interval [low,high].

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Example:

cout << VectorXi::LinSpaced(4,7,10).transpose() << endl;
cout << VectorXd::LinSpaced(5,0.0,1.0).transpose() << endl;

Output:

 7  8  9 10
   0 0.25  0.5 0.75    1
See also:
setLinSpaced(Index,const Scalar&,const Scalar&), LinSpaced(Sequential_t,Index,const Scalar&,const Scalar&,Index), CwiseNullaryOp
const DenseBase< Derived >::SequentialLinSpacedReturnType LinSpaced ( Sequential_t  ,
const Scalar &  low,
const Scalar &  high 
) [inline, static]

Sets a linearly space vector.

The function generates 'size' equally spaced values in the closed interval [low,high]. This particular version of LinSpaced() uses sequential access, i.e. vector access is assumed to be a(0), a(1), ..., a(size). This assumption allows for better vectorization and yields faster code than the random access version.This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.Example:

cout << VectorXi::LinSpaced(Sequential,4,7,10).transpose() << endl;
cout << VectorXd::LinSpaced(Sequential,5,0.0,1.0).transpose() << endl;

Output:

 7  8  9 10
   0 0.25  0.5 0.75    1
See also:
setLinSpaced(Index,const Scalar&,const Scalar&), LinSpaced(Index,Scalar,Scalar), CwiseNullaryOp
Special version for fixed size types which does not require the size parameter.

const DenseBase< Derived >::RandomAccessLinSpacedReturnType LinSpaced ( const Scalar &  low,
const Scalar &  high 
) [inline, static]

Sets a linearly space vector.

The function generates 'size' equally spaced values in the closed interval [low,high].This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.Example:

cout << VectorXi::LinSpaced(4,7,10).transpose() << endl;
cout << VectorXd::LinSpaced(5,0.0,1.0).transpose() << endl;

Output:

 7  8  9 10
   0 0.25  0.5 0.75    1
See also:
setLinSpaced(Index,const Scalar&,const Scalar&), LinSpaced(Sequential_t,Index,const Scalar&,const Scalar&,Index), CwiseNullaryOp
Special version for fixed size types which does not require the size parameter.

internal::traits< Derived >::Scalar maxCoeff ( ) const [inline]
Returns:
the maximum of all coefficients of *this
internal::traits< Derived >::Scalar maxCoeff ( IndexType *  row,
IndexType *  col 
) const
Returns:
the maximum of all coefficients of *this and puts in *row and *col its location.
See also:
DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::visitor(), DenseBase::maxCoeff()
internal::traits< Derived >::Scalar maxCoeff ( IndexType *  index) const
Returns:
the maximum of all coefficients of *this and puts in *index its location.
See also:
DenseBase::maxCoeff(IndexType*,IndexType*), DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::visitor(), DenseBase::maxCoeff()
internal::traits< Derived >::Scalar mean ( ) const [inline]
Returns:
the mean of all coefficients of *this
See also:
trace(), prod(), sum()
ColsBlockXpr middleCols ( Index  startCol,
Index  numCols 
) [inline]
Returns:
a block consisting of a range of columns of *this.
Parameters:
startColthe index of the first column in the block
numColsthe number of columns in the block

Example:

#include <Eigen/Core>
#include <iostream>

using namespace Eigen;
using namespace std;

int main(void)
{
    int const N = 5;
    MatrixXi A(N,N);
    A.setRandom();
    cout << "A =\n" << A << '\n' << endl;
    cout << "A(1..3,:) =\n" << A.middleCols(1,3) << endl;
    return 0;
}

Output:

A =
  7  -6   0   9 -10
 -2  -3   3   3  -5
  6   6  -3   5  -8
  6  -5   0  -8   6
  9   1   9   2  -7

A(1..3,:) =
-6  0  9
-3  3  3
 6 -3  5
-5  0 -8
 1  9  2
See also:
class Block, block(Index,Index,Index,Index)
ConstColsBlockXpr middleCols ( Index  startCol,
Index  numCols 
) const [inline]

This is the const version of middleCols(Index,Index).

NColsBlockXpr<N>::Type middleCols ( Index  startCol) [inline]
Returns:
a block consisting of a range of columns of *this.
Template Parameters:
Nthe number of columns in the block
Parameters:
startColthe index of the first column in the block

Example:

#include <Eigen/Core>
#include <iostream>

using namespace Eigen;
using namespace std;

int main(void)
{
    int const N = 5;
    MatrixXi A(N,N);
    A.setRandom();
    cout << "A =\n" << A << '\n' << endl;
    cout << "A(:,1..3) =\n" << A.middleCols<3>(1) << endl;
    return 0;
}

Output:

A =
  7  -6   0   9 -10
 -2  -3   3   3  -5
  6   6  -3   5  -8
  6  -5   0  -8   6
  9   1   9   2  -7

A(:,1..3) =
-6  0  9
-3  3  3
 6 -3  5
-5  0 -8
 1  9  2
See also:
class Block, block(Index,Index,Index,Index)
ConstNColsBlockXpr<N>::Type middleCols ( Index  startCol) const [inline]

This is the const version of middleCols<int>().

RowsBlockXpr middleRows ( Index  startRow,
Index  numRows 
) [inline]
Returns:
a block consisting of a range of rows of *this.
Parameters:
startRowthe index of the first row in the block
numRowsthe number of rows in the block

Example:

#include <Eigen/Core>
#include <iostream>

using namespace Eigen;
using namespace std;

int main(void)
{
    int const N = 5;
    MatrixXi A(N,N);
    A.setRandom();
    cout << "A =\n" << A << '\n' << endl;
    cout << "A(2..3,:) =\n" << A.middleRows(2,2) << endl;
    return 0;
}

Output:

A =
  7  -6   0   9 -10
 -2  -3   3   3  -5
  6   6  -3   5  -8
  6  -5   0  -8   6
  9   1   9   2  -7

A(2..3,:) =
 6  6 -3  5 -8
 6 -5  0 -8  6
See also:
class Block, block(Index,Index,Index,Index)
ConstRowsBlockXpr middleRows ( Index  startRow,
Index  numRows 
) const [inline]

This is the const version of middleRows(Index,Index).

NRowsBlockXpr<N>::Type middleRows ( Index  startRow) [inline]
Returns:
a block consisting of a range of rows of *this.
Template Parameters:
Nthe number of rows in the block
Parameters:
startRowthe index of the first row in the block

Example:

#include <Eigen/Core>
#include <iostream>

using namespace Eigen;
using namespace std;

int main(void)
{
    int const N = 5;
    MatrixXi A(N,N);
    A.setRandom();
    cout << "A =\n" << A << '\n' << endl;
    cout << "A(1..3,:) =\n" << A.middleRows<3>(1) << endl;
    return 0;
}

Output:

A =
  7  -6   0   9 -10
 -2  -3   3   3  -5
  6   6  -3   5  -8
  6  -5   0  -8   6
  9   1   9   2  -7

A(1..3,:) =
-2 -3  3  3 -5
 6  6 -3  5 -8
 6 -5  0 -8  6
See also:
class Block, block(Index,Index,Index,Index)
ConstNRowsBlockXpr<N>::Type middleRows ( Index  startRow) const [inline]

This is the const version of middleRows<int>().

internal::traits< Derived >::Scalar minCoeff ( ) const [inline]
Returns:
the minimum of all coefficients of *this
internal::traits< Derived >::Scalar minCoeff ( IndexType *  row,
IndexType *  col 
) const
Returns:
the minimum of all coefficients of *this and puts in *row and *col its location.
See also:
DenseBase::minCoeff(Index*), DenseBase::maxCoeff(Index*,Index*), DenseBase::visitor(), DenseBase::minCoeff()
internal::traits< Derived >::Scalar minCoeff ( IndexType *  index) const
Returns:
the minimum of all coefficients of *this and puts in *index its location.
See also:
DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::maxCoeff(IndexType*,IndexType*), DenseBase::visitor(), DenseBase::minCoeff()
const NestByValue< Derived > nestByValue ( ) const [inline]
Returns:
an expression of the temporary version of *this.
Index nonZeros ( ) const [inline]
Returns:
the number of nonzero coefficients which is in practice the number of stored coefficients.
const CwiseNullaryOp< CustomNullaryOp, Derived > NullaryExpr ( Index  rows,
Index  cols,
const CustomNullaryOp &  func 
) [inline, static]
Returns:
an expression of a matrix defined by a custom functor func

The parameters rows and cols are the number of rows and of columns of the returned matrix. Must be compatible with this MatrixBase type.

This variant is meant to be used for dynamic-size matrix types. For fixed-size types, it is redundant to pass rows and cols as arguments, so Zero() should be used instead.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
const CwiseNullaryOp< CustomNullaryOp, Derived > NullaryExpr ( Index  size,
const CustomNullaryOp &  func 
) [inline, static]
Returns:
an expression of a matrix defined by a custom functor func

The parameter size is the size of the returned vector. Must be compatible with this MatrixBase type.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

This variant is meant to be used for dynamic-size vector types. For fixed-size types, it is redundant to pass size as argument, so Zero() should be used instead.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
const CwiseNullaryOp< CustomNullaryOp, Derived > NullaryExpr ( const CustomNullaryOp &  func) [inline, static]
Returns:
an expression of a matrix defined by a custom functor func

This variant is only for fixed-size DenseBase types. For dynamic-size types, you need to use the variants taking size arguments.

The template parameter CustomNullaryOp is the type of the functor.

See also:
class CwiseNullaryOp
const DenseBase< Derived >::ConstantReturnType Ones ( Index  rows,
Index  cols 
) [inline, static]
Returns:
an expression of a matrix where all coefficients equal one.

The parameters rows and cols are the number of rows and of columns of the returned matrix. Must be compatible with this MatrixBase type.

This variant is meant to be used for dynamic-size matrix types. For fixed-size types, it is redundant to pass rows and cols as arguments, so Ones() should be used instead.

Example:

cout << MatrixXi::Ones(2,3) << endl;

Output:

1 1 1
1 1 1
See also:
Ones(), Ones(Index), isOnes(), class Ones
const DenseBase< Derived >::ConstantReturnType Ones ( Index  size) [inline, static]
Returns:
an expression of a vector where all coefficients equal one.

The parameter size is the size of the returned vector. Must be compatible with this MatrixBase type.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

This variant is meant to be used for dynamic-size vector types. For fixed-size types, it is redundant to pass size as argument, so Ones() should be used instead.

Example:

cout << 6 * RowVectorXi::Ones(4) << endl;
cout << VectorXf::Ones(2) << endl;

Output:

6 6 6 6
1
1
See also:
Ones(), Ones(Index,Index), isOnes(), class Ones
const DenseBase< Derived >::ConstantReturnType Ones ( ) [inline, static]
Returns:
an expression of a fixed-size matrix or vector where all coefficients equal one.

This variant is only for fixed-size MatrixBase types. For dynamic-size types, you need to use the variants taking size arguments.

Example:

cout << Matrix2d::Ones() << endl;
cout << 6 * RowVector4i::Ones() << endl;

Output:

1 1
1 1
6 6 6 6
See also:
Ones(Index), Ones(Index,Index), isOnes(), class Ones
CommaInitializer< Derived > operator<< ( const Scalar &  s) [inline]

Convenient operator to set the coefficients of a matrix.

The coefficients must be provided in a row major order and exactly match the size of the matrix. Otherwise an assertion is raised.

Example:

Matrix3i m1;
m1 << 1, 2, 3,
      4, 5, 6,
      7, 8, 9;
cout << m1 << endl << endl;
Matrix3i m2 = Matrix3i::Identity();
m2.block(0,0, 2,2) << 10, 11, 12, 13;
cout << m2 << endl << endl;
Vector2i v1;
v1 << 14, 15;
m2 << v1.transpose(), 16,
      v1, m1.block(1,1,2,2);
cout << m2 << endl;

Output:

1 2 3
4 5 6
7 8 9

10 11  0
12 13  0
 0  0  1

14 15 16
14  5  6
15  8  9
See also:
CommaInitializer::finished(), class CommaInitializer
CommaInitializer< Derived > operator<< ( const DenseBase< OtherDerived > &  other) [inline]
Derived& operator= ( const DenseBase< OtherDerived > &  other)
Derived& operator= ( const DenseBase< Derived > &  other)

Special case of the template operator=, in order to prevent the compiler from generating a default operator= (issue hit with g++ 4.1)

Derived & operator= ( const EigenBase< OtherDerived > &  other)

Copies the generic expression other into *this.

The expression must provide a (templated) evalTo(Derived& dst) const function which does the actual job. In practice, this allows any user to write its own special matrix without having to modify MatrixBase

Returns:
a reference to *this.

Reimplemented in MatrixBase< Derived >, MatrixBase< TriangularProduct< Mode, false, Lhs, true, Rhs, false > >, MatrixBase< DenseTimeSparseSelfAdjointProduct< Lhs, Rhs, UpLo > >, MatrixBase< ScaledProduct< NestedProduct > >, MatrixBase< SelfadjointProductMatrix< Lhs, LhsMode, false, Rhs, 0, true > >, MatrixBase< MatrixWrapper< ExpressionType > >, MatrixBase< SparseSelfAdjointTimeDenseProduct< Lhs, Rhs, UpLo > >, MatrixBase< GeneralProduct< Lhs, Rhs, OuterProduct > >, MatrixBase< Flagged< ExpressionType, Added, Removed > >, MatrixBase< SelfadjointProductMatrix< Lhs, LhsMode, false, Rhs, RhsMode, false > >, MatrixBase< GeneralProduct< Lhs, Rhs, GemmProduct > >, MatrixBase< TriangularProduct< Mode, LhsIsTriangular, Lhs, false, Rhs, false > >, MatrixBase< SelfadjointProductMatrix< Lhs, 0, true, Rhs, RhsMode, false > >, MatrixBase< Homogeneous< MatrixType, _Direction > >, MatrixBase< SparseTimeDenseProduct< Lhs, Rhs > >, MatrixBase< DenseTimeSparseProduct< Lhs, Rhs > >, MatrixBase< CoeffBasedProduct< LhsNested, RhsNested, NestingFlags > >, MatrixBase< Minor< MatrixType > >, MatrixBase< GeneralProduct< Lhs, Rhs, GemvProduct > >, MatrixBase< DiagonalProduct< MatrixType, DiagonalType, ProductOrder > >, and MatrixBase< TriangularProduct< Mode, true, Lhs, false, Rhs, true > >.

Index outerSize ( ) const [inline]
Returns:
true if either the number of rows or the number of columns is equal to 1. In other words, this function returns
 rows()==1 || cols()==1 
See also:
rows(), cols(), IsVectorAtCompileTime.
Returns:
the outer size.
Note:
For a vector, this returns just 1. For a matrix (non-vector), this is the major dimension with respect to the storage order, i.e., the number of columns for a column-major matrix, and the number of rows for a row-major matrix.
internal::traits< Derived >::Scalar prod ( ) const [inline]
Returns:
the product of all coefficients of *this

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the product of all the coefficients:" << endl << m.prod() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the product of all the coefficients:
0.0019
See also:
sum(), mean(), trace()
const CwiseNullaryOp< internal::scalar_random_op< typename internal::traits< Derived >::Scalar >, Derived > Random ( Index  rows,
Index  cols 
) [inline, static]
Returns:
a random matrix expression

The parameters rows and cols are the number of rows and of columns of the returned matrix. Must be compatible with this MatrixBase type.

This variant is meant to be used for dynamic-size matrix types. For fixed-size types, it is redundant to pass rows and cols as arguments, so Random() should be used instead.

Example:

cout << MatrixXi::Random(2,3) << endl;

Output:

 7  6  9
-2  6 -6

This expression has the "evaluate before nesting" flag so that it will be evaluated into a temporary matrix whenever it is nested in a larger expression. This prevents unexpected behavior with expressions involving random matrices.

See also:
MatrixBase::setRandom(), MatrixBase::Random(Index), MatrixBase::Random()
const CwiseNullaryOp< internal::scalar_random_op< typename internal::traits< Derived >::Scalar >, Derived > Random ( Index  size) [inline, static]
Returns:
a random vector expression

The parameter size is the size of the returned vector. Must be compatible with this MatrixBase type.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

This variant is meant to be used for dynamic-size vector types. For fixed-size types, it is redundant to pass size as argument, so Random() should be used instead.

Example:

cout << VectorXi::Random(2) << endl;

Output:

7
-2

This expression has the "evaluate before nesting" flag so that it will be evaluated into a temporary vector whenever it is nested in a larger expression. This prevents unexpected behavior with expressions involving random matrices.

See also:
MatrixBase::setRandom(), MatrixBase::Random(Index,Index), MatrixBase::Random()
const CwiseNullaryOp< internal::scalar_random_op< typename internal::traits< Derived >::Scalar >, Derived > Random ( ) [inline, static]
Returns:
a fixed-size random matrix or vector expression

This variant is only for fixed-size MatrixBase types. For dynamic-size types, you need to use the variants taking size arguments.

Example:

cout << 100 * Matrix2i::Random() << endl;

Output:

700 600
-200 600

This expression has the "evaluate before nesting" flag so that it will be evaluated into a temporary matrix whenever it is nested in a larger expression. This prevents unexpected behavior with expressions involving random matrices.

See also:
MatrixBase::setRandom(), MatrixBase::Random(Index,Index), MatrixBase::Random(Index)
const Replicate< Derived, RowFactor, ColFactor > replicate ( ) const [inline]
Returns:
an expression of the replication of *this

Example:

MatrixXi m = MatrixXi::Random(2,3);
cout << "Here is the matrix m:" << endl << m << endl;
cout << "m.replicate<3,2>() = ..." << endl;
cout << m.replicate<3,2>() << endl;

Output:

Here is the matrix m:
 7  6  9
-2  6 -6
m.replicate<3,2>() = ...
 7  6  9  7  6  9
-2  6 -6 -2  6 -6
 7  6  9  7  6  9
-2  6 -6 -2  6 -6
 7  6  9  7  6  9
-2  6 -6 -2  6 -6
See also:
VectorwiseOp::replicate(), DenseBase::replicate(Index,Index), class Replicate
const Replicate< Derived, Dynamic, Dynamic > replicate ( Index  rowFactor,
Index  colFactor 
) const [inline]
Returns:
an expression of the replication of *this

Example:

Vector3i v = Vector3i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "v.replicate(2,5) = ..." << endl;
cout << v.replicate(2,5) << endl;

Output:

Here is the vector v:
7
-2
6
v.replicate(2,5) = ...
 7  7  7  7  7
-2 -2 -2 -2 -2
 6  6  6  6  6
 7  7  7  7  7
-2 -2 -2 -2 -2
 6  6  6  6  6
See also:
VectorwiseOp::replicate(), DenseBase::replicate<int,int>(), class Replicate
void resize ( Index  size) [inline]

Only plain matrices/arrays, not expressions, may be resized; therefore the only useful resize methods are Matrix::resize() and Array::resize(). The present method only asserts that the new size equals the old size, and does nothing else.

void resize ( Index  rows,
Index  cols 
) [inline]

Only plain matrices/arrays, not expressions, may be resized; therefore the only useful resize methods are Matrix::resize() and Array::resize(). The present method only asserts that the new size equals the old size, and does nothing else.

DenseBase< Derived >::ReverseReturnType reverse ( ) [inline]
Returns:
an expression of the reverse of *this.

Example:

MatrixXi m = MatrixXi::Random(3,4);
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the reverse of m:" << endl << m.reverse() << endl;
cout << "Here is the coefficient (1,0) in the reverse of m:" << endl
     << m.reverse()(1,0) << endl;
cout << "Let us overwrite this coefficient with the value 4." << endl;
m.reverse()(1,0) = 4;
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  6 -3  1
-2  9  6  0
 6 -6 -5  3
Here is the reverse of m:
 3 -5 -6  6
 0  6  9 -2
 1 -3  6  7
Here is the coefficient (1,0) in the reverse of m:
0
Let us overwrite this coefficient with the value 4.
Now the matrix m is:
 7  6 -3  1
-2  9  6  4
 6 -6 -5  3
const DenseBase< Derived >::ConstReverseReturnType reverse ( ) const [inline]

This is the const version of reverse().

void reverseInPlace ( ) [inline]

This is the "in place" version of reverse: it reverses *this.

In most cases it is probably better to simply use the reversed expression of a matrix. However, when reversing the matrix data itself is really needed, then this "in-place" version is probably the right choice because it provides the following additional features:

  • less error prone: doing the same operation with .reverse() requires special care:
     m = m.reverse().eval(); 
    
  • this API allows to avoid creating a temporary (the current implementation creates a temporary, but that could be avoided using swap)
  • it allows future optimizations (cache friendliness, etc.)
See also:
reverse()
ColsBlockXpr rightCols ( Index  n) [inline]
Returns:
a block consisting of the right columns of *this.
Parameters:
nthe number of columns in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.rightCols(2):" << endl;
cout << a.rightCols(2) << endl;
a.rightCols(2).setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.rightCols(2):
-5 -3
 1  0
 0  9
 3  9
Now the array a is:
 7  9  0  0
-2 -6  0  0
 6 -3  0  0
 6  6  0  0
See also:
class Block, block(Index,Index,Index,Index)
ConstColsBlockXpr rightCols ( Index  n) const [inline]

This is the const version of rightCols(Index).

NColsBlockXpr<N>::Type rightCols ( ) [inline]
Returns:
a block consisting of the right columns of *this.
Template Parameters:
Nthe number of columns in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.rightCols<2>():" << endl;
cout << a.rightCols<2>() << endl;
a.rightCols<2>().setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.rightCols<2>():
-5 -3
 1  0
 0  9
 3  9
Now the array a is:
 7  9  0  0
-2 -6  0  0
 6 -3  0  0
 6  6  0  0
See also:
class Block, block(Index,Index,Index,Index)
ConstNColsBlockXpr<N>::Type rightCols ( ) const [inline]

This is the const version of rightCols<int>().

RowXpr row ( Index  i) [inline]
Returns:
an expression of the i-th row of *this. Note that the numbering starts at 0.

Example:

Matrix3d m = Matrix3d::Identity();
m.row(1) = Vector3d(4,5,6);
cout << m << endl;

Output:

1 0 0
4 5 6
0 0 1
See also:
col(), class Block
ConstRowXpr row ( Index  i) const [inline]

This is the const version of row().

const DenseBase< Derived >::ConstRowwiseReturnType rowwise ( ) const [inline]
Returns:
a VectorwiseOp wrapper of *this providing additional partial reduction operations

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the sum of each row:" << endl << m.rowwise().sum() << endl;
cout << "Here is the maximum absolute value of each row:"
     << endl << m.cwiseAbs().rowwise().maxCoeff() << endl;

Output:

Here is the matrix m:
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
Here is the sum of each row:
0.948
1.15
-0.483
Here is the maximum absolute value of each row:
0.68
0.823
0.605
See also:
colwise(), class VectorwiseOp
DenseBase< Derived >::RowwiseReturnType rowwise ( ) [inline]
Returns:
a writable VectorwiseOp wrapper of *this providing additional partial reduction operations
See also:
colwise(), class VectorwiseOp
DenseBase< Derived >::SegmentReturnType segment ( Index  start,
Index  size 
) [inline]
Returns:
a dynamic-size expression of a segment (i.e. a vector block) in *this.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Parameters:
startthe first coefficient in the segment
sizethe number of coefficients in the segment

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.segment(1, 2):" << endl << v.segment(1, 2) << endl;
v.segment(1, 2).setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.segment(1, 2):
-2 6
Now the vector v is:
7 0 0 6
Note:
Even though the returned expression has dynamic size, in the case when it is applied to a fixed-size vector, it inherits a fixed maximal size, which means that evaluating it does not cause a dynamic memory allocation.
See also:
class Block, segment(Index)
DenseBase< Derived >::ConstSegmentReturnType segment ( Index  start,
Index  size 
) const [inline]

This is the const version of segment(Index,Index).

DenseBase< Derived >::template FixedSegmentReturnType< Size >::Type segment ( Index  start) [inline]
Returns:
a fixed-size expression of a segment (i.e. a vector block) in *this

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

The template parameter Size is the number of coefficients in the block

Parameters:
startthe index of the first element of the sub-vector

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.segment<2>(1):" << endl << v.segment<2>(1) << endl;
v.segment<2>(2).setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.segment<2>(1):
-2 6
Now the vector v is:
 7 -2  0  0
See also:
class Block
DenseBase< Derived >::template ConstFixedSegmentReturnType< Size >::Type segment ( Index  start) const [inline]

This is the const version of segment<int>(Index).

const Select< Derived, ThenDerived, ElseDerived > select ( const DenseBase< ThenDerived > &  thenMatrix,
const DenseBase< ElseDerived > &  elseMatrix 
) const [inline]
Returns:
a matrix where each coefficient (i,j) is equal to thenMatrix(i,j) if *this(i,j), and elseMatrix(i,j) otherwise.

Example:

MatrixXi m(3, 3);
m << 1, 2, 3,
     4, 5, 6,
     7, 8, 9;
m = (m.array() >= 5).select(-m, m);
cout << m << endl;

Output:

 1  2  3
 4 -5 -6
-7 -8 -9
See also:
class Select
const Select< Derived, ThenDerived, typename ThenDerived::ConstantReturnType > select ( const DenseBase< ThenDerived > &  thenMatrix,
typename ThenDerived::Scalar  elseScalar 
) const [inline]

Version of DenseBase::select(const DenseBase&, const DenseBase&) with the else expression being a scalar value.

See also:
DenseBase::select(const DenseBase<ThenDerived>&, const DenseBase<ElseDerived>&) const, class Select
const Select< Derived, typename ElseDerived::ConstantReturnType, ElseDerived > select ( typename ElseDerived::Scalar  thenScalar,
const DenseBase< ElseDerived > &  elseMatrix 
) const [inline]

Version of DenseBase::select(const DenseBase&, const DenseBase&) with the then expression being a scalar value.

See also:
DenseBase::select(const DenseBase<ThenDerived>&, const DenseBase<ElseDerived>&) const, class Select
Derived & setConstant ( const Scalar &  value) [inline]

Sets all coefficients in this expression to value.

See also:
fill(), setConstant(Index,const Scalar&), setConstant(Index,Index,const Scalar&), setZero(), setOnes(), Constant(), class CwiseNullaryOp, setZero(), setOnes()
Derived & setLinSpaced ( Index  size,
const Scalar &  low,
const Scalar &  high 
) [inline]

Sets a linearly space vector.

The function generates 'size' equally spaced values in the closed interval [low,high].

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Example:

VectorXf v;
v.setLinSpaced(5,0.5f,1.5f).transpose();
cout << v << endl;

Output:

0.5
0.75
1
1.25
1.5
See also:
CwiseNullaryOp
Derived & setOnes ( ) [inline]

Sets all coefficients in this expression to one.

Example:

Matrix4i m = Matrix4i::Random();
m.row(1).setOnes();
cout << m << endl;

Output:

 7  9 -5 -3
 1  1  1  1
 6 -3  0  9
 6  6  3  9
See also:
class CwiseNullaryOp, Ones()
Derived & setRandom ( ) [inline]

Sets all coefficients in this expression to random values.

Example:

Matrix4i m = Matrix4i::Zero();
m.col(1).setRandom();
cout << m << endl;

Output:

 0  7  0  0
 0 -2  0  0
 0  6  0  0
 0  6  0  0
See also:
class CwiseNullaryOp, setRandom(Index), setRandom(Index,Index)
Derived & setZero ( ) [inline]

Sets all coefficients in this expression to zero.

Example:

Matrix4i m = Matrix4i::Random();
m.row(1).setZero();
cout << m << endl;

Output:

 7  9 -5 -3
 0  0  0  0
 6 -3  0  9
 6  6  3  9
See also:
class CwiseNullaryOp, Zero()
internal::traits< Derived >::Scalar sum ( ) const [inline]
Returns:
the sum of all coefficients of *this
See also:
trace(), prod(), mean()
void swap ( const DenseBase< OtherDerived > &  other,
int  = OtherDerived::ThisConstantIsPrivateInPlainObjectBase 
) [inline]

swaps *this with the expression other.

void swap ( PlainObjectBase< OtherDerived > &  other) [inline]

swaps *this with the matrix or array other.

DenseBase< Derived >::SegmentReturnType tail ( Index  size) [inline]
Returns:
a dynamic-size expression of the last coefficients of *this.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Parameters:
sizethe number of coefficients in the block

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.tail(2):" << endl << v.tail(2) << endl;
v.tail(2).setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.tail(2):
6 6
Now the vector v is:
 7 -2  0  0
Note:
Even though the returned expression has dynamic size, in the case when it is applied to a fixed-size vector, it inherits a fixed maximal size, which means that evaluating it does not cause a dynamic memory allocation.
See also:
class Block, block(Index,Index)
DenseBase< Derived >::ConstSegmentReturnType tail ( Index  size) const [inline]

This is the const version of tail(Index).

DenseBase< Derived >::template FixedSegmentReturnType< Size >::Type tail ( ) [inline]
Returns:
a fixed-size expression of the last coefficients of *this.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

The template parameter Size is the number of coefficients in the block

Example:

RowVector4i v = RowVector4i::Random();
cout << "Here is the vector v:" << endl << v << endl;
cout << "Here is v.tail(2):" << endl << v.tail<2>() << endl;
v.tail<2>().setZero();
cout << "Now the vector v is:" << endl << v << endl;

Output:

Here is the vector v:
 7 -2  6  6
Here is v.tail(2):
6 6
Now the vector v is:
 7 -2  0  0
See also:
class Block
DenseBase< Derived >::template ConstFixedSegmentReturnType< Size >::Type tail ( ) const [inline]

This is the const version of tail<int>.

Block<Derived> topLeftCorner ( Index  cRows,
Index  cCols 
) [inline]
Returns:
a dynamic-size expression of a top-left corner of *this.
Parameters:
cRowsthe number of rows in the corner
cColsthe number of columns in the corner

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.topLeftCorner(2, 2):" << endl;
cout << m.topLeftCorner(2, 2) << endl;
m.topLeftCorner(2, 2).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.topLeftCorner(2, 2):
 7  9
-2 -6
Now the matrix m is:
 0  0 -5 -3
 0  0  1  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived> topLeftCorner ( Index  cRows,
Index  cCols 
) const [inline]

This is the const version of topLeftCorner(Index, Index).

Block<Derived, CRows, CCols> topLeftCorner ( ) [inline]
Returns:
an expression of a fixed-size top-left corner of *this.

The template parameters CRows and CCols are the number of rows and columns in the corner.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.topLeftCorner<2,2>():" << endl;
cout << m.topLeftCorner<2,2>() << endl;
m.topLeftCorner<2,2>().setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.topLeftCorner<2,2>():
 7  9
-2 -6
Now the matrix m is:
 0  0 -5 -3
 0  0  1  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived, CRows, CCols> topLeftCorner ( ) const [inline]

This is the const version of topLeftCorner<int, int>().

Block<Derived> topRightCorner ( Index  cRows,
Index  cCols 
) [inline]
Returns:
a dynamic-size expression of a top-right corner of *this.
Parameters:
cRowsthe number of rows in the corner
cColsthe number of columns in the corner

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.topRightCorner(2, 2):" << endl;
cout << m.topRightCorner(2, 2) << endl;
m.topRightCorner(2, 2).setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.topRightCorner(2, 2):
-5 -3
 1  0
Now the matrix m is:
 7  9  0  0
-2 -6  0  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived> topRightCorner ( Index  cRows,
Index  cCols 
) const [inline]

This is the const version of topRightCorner(Index, Index).

Block<Derived, CRows, CCols> topRightCorner ( ) [inline]
Returns:
an expression of a fixed-size top-right corner of *this.

The template parameters CRows and CCols are the number of rows and columns in the corner.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is m.topRightCorner<2,2>():" << endl;
cout << m.topRightCorner<2,2>() << endl;
m.topRightCorner<2,2>().setZero();
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is m.topRightCorner<2,2>():
-5 -3
 1  0
Now the matrix m is:
 7  9  0  0
-2 -6  0  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
const Block<const Derived, CRows, CCols> topRightCorner ( ) const [inline]

This is the const version of topRightCorner<int, int>().

RowsBlockXpr topRows ( Index  n) [inline]
Returns:
a block consisting of the top rows of *this.
Parameters:
nthe number of rows in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.topRows(2):" << endl;
cout << a.topRows(2) << endl;
a.topRows(2).setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.topRows(2):
 7  9 -5 -3
-2 -6  1  0
Now the array a is:
 0  0  0  0
 0  0  0  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
ConstRowsBlockXpr topRows ( Index  n) const [inline]

This is the const version of topRows(Index).

NRowsBlockXpr<N>::Type topRows ( ) [inline]
Returns:
a block consisting of the top rows of *this.
Template Parameters:
Nthe number of rows in the block

Example:

Array44i a = Array44i::Random();
cout << "Here is the array a:" << endl << a << endl;
cout << "Here is a.topRows<2>():" << endl;
cout << a.topRows<2>() << endl;
a.topRows<2>().setZero();
cout << "Now the array a is:" << endl << a << endl;

Output:

Here is the array a:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here is a.topRows<2>():
 7  9 -5 -3
-2 -6  1  0
Now the array a is:
 0  0  0  0
 0  0  0  0
 6 -3  0  9
 6  6  3  9
See also:
class Block, block(Index,Index,Index,Index)
ConstNRowsBlockXpr<N>::Type topRows ( ) const [inline]

This is the const version of topRows<int>().

Transpose< Derived > transpose ( ) [inline]
Returns:
an expression of the transpose of *this.

Example:

Matrix2i m = Matrix2i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the transpose of m:" << endl << m.transpose() << endl;
cout << "Here is the coefficient (1,0) in the transpose of m:" << endl
     << m.transpose()(1,0) << endl;
cout << "Let us overwrite this coefficient with the value 0." << endl;
m.transpose()(1,0) = 0;
cout << "Now the matrix m is:" << endl << m << endl;

Output:

Here is the matrix m:
7 6
-2 6
Here is the transpose of m:
 7 -2
 6  6
Here is the coefficient (1,0) in the transpose of m:
6
Let us overwrite this coefficient with the value 0.
Now the matrix m is:
7 0
-2 6
Warning:
If you want to replace a matrix by its own transpose, do NOT do this:
 m = m.transpose(); // bug!!! caused by aliasing effect
Instead, use the transposeInPlace() method:
 m.transposeInPlace();
which gives Eigen good opportunities for optimization, or alternatively you can also do:
 m = m.transpose().eval();
See also:
transposeInPlace(), adjoint()
const DenseBase< Derived >::ConstTransposeReturnType transpose ( ) const [inline]

This is the const version of transpose().

Make sure you read the warning for transpose() !

See also:
transposeInPlace(), adjoint()
void transposeInPlace ( ) [inline]

This is the "in place" version of transpose(): it replaces *this by its own transpose. Thus, doing

 m.transposeInPlace();

has the same effect on m as doing

 m = m.transpose().eval();

and is faster and also safer because in the latter line of code, forgetting the eval() results in a bug caused by aliasing.

Notice however that this method is only useful if you want to replace a matrix by its own transpose. If you just need the transpose of a matrix, use transpose().

Note:
if the matrix is not square, then *this must be a resizable matrix.
See also:
transpose(), adjoint(), adjointInPlace()
CoeffReturnType value ( ) const [inline]
Returns:
the unique coefficient of a 1x1 expression
void visit ( Visitor &  visitor) const

Applies the visitor visitor to the whole coefficients of the matrix or vector.

The template parameter Visitor is the type of the visitor and provides the following interface:

 struct MyVisitor {
   // called for the first coefficient
   void init(const Scalar& value, Index i, Index j);
   // called for all other coefficients
   void operator() (const Scalar& value, Index i, Index j);
 };
Note:
compared to one or two for loops, visitors offer automatic unrolling for small fixed size matrix.
See also:
minCoeff(Index*,Index*), maxCoeff(Index*,Index*), DenseBase::redux()
const DenseBase< Derived >::ConstantReturnType Zero ( Index  rows,
Index  cols 
) [inline, static]
Returns:
an expression of a zero matrix.

The parameters rows and cols are the number of rows and of columns of the returned matrix. Must be compatible with this MatrixBase type.

This variant is meant to be used for dynamic-size matrix types. For fixed-size types, it is redundant to pass rows and cols as arguments, so Zero() should be used instead.

Example:

cout << MatrixXi::Zero(2,3) << endl;

Output:

0 0 0
0 0 0
See also:
Zero(), Zero(Index)
const DenseBase< Derived >::ConstantReturnType Zero ( Index  size) [inline, static]
Returns:
an expression of a zero vector.

The parameter size is the size of the returned vector. Must be compatible with this MatrixBase type.

This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

This variant is meant to be used for dynamic-size vector types. For fixed-size types, it is redundant to pass size as argument, so Zero() should be used instead.

Example:

cout << RowVectorXi::Zero(4) << endl;
cout << VectorXf::Zero(2) << endl;

Output:

0 0 0 0
0
0
See also:
Zero(), Zero(Index,Index)
const DenseBase< Derived >::ConstantReturnType Zero ( ) [inline, static]
Returns:
an expression of a fixed-size zero matrix or vector.

This variant is only for fixed-size MatrixBase types. For dynamic-size types, you need to use the variants taking size arguments.

Example:

cout << Matrix2d::Zero() << endl;
cout << RowVector4i::Zero() << endl;

Output:

0 0
0 0
0 0 0 0
See also:
Zero(Index), Zero(Index,Index)

Friends And Related Function Documentation

std::ostream & operator<< ( std::ostream &  s,
const DenseBase< Derived > &  m 
) [related]

Outputs the matrix, to the given stream.

If you wish to print the matrix with a format different than the default, use DenseBase::format().

It is also possible to change the default format by defining EIGEN_DEFAULT_IO_FORMAT before including Eigen headers. If not defined, this will automatically be defined to Eigen::IOFormat(), that is the Eigen::IOFormat with default parameters.

See also:
DenseBase::format()

The documentation for this class was generated from the following files: