template<typename Derived>
Eigen::MatrixBase class

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

Template parameters
Derived is the derived type, e.g. a matrix type, or an expression, etc.

This class is the base that is inherited by all matrix, vector, and related expression types. Most of the Eigen API is contained in this class, and its base classes. Other important classes for the Eigen API are Matrix, and VectorwiseOp.

Note that some methods are defined in other modules such as the LU module LU module for all functions related to matrix inversions.

When writing a function taking Eigen objects as argument, if you want your function to take as argument any matrix, vector, or expression, just let it take a MatrixBase argument. As an example, here is a function printFirstRow which, given a matrix, vector, or expression x, prints the first row of x.

template<typename Derived>
void printFirstRow(const Eigen::MatrixBase<Derived>& x)
{
  cout << x.row(0) << endl;
}

This class can be extended with the help of the plugin mechanism described on the page Extending MatrixBase (and other classes) by defining the preprocessor symbol EIGEN_MATRIXBASE_PLUGIN.

Base classes

template<typename Derived>
class DenseBase
Base class for all dense matrices, vectors, and arrays.

Derived classes

template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
struct dense_xpr_base_dispatcher<Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>>

Public types

using CwiseAbs2ReturnType = CwiseUnaryOp<internal::scalar_abs2_op<Scalar>, const Derived>
using CwiseAbsReturnType = CwiseUnaryOp<internal::scalar_abs_op<Scalar>, const Derived>
using CwiseInverseReturnType = CwiseUnaryOp<internal::scalar_inverse_op<Scalar>, const Derived>
using CwiseScalarEqualReturnType = CwiseBinaryOp<internal::scalar_cmp_op<Scalar, Scalar, internal::cmp_EQ>, const Derived, const ConstantReturnType>
using CwiseSignReturnType = CwiseUnaryOp<internal::scalar_sign_op<Scalar>, const Derived>
using CwiseSqrtReturnType = CwiseUnaryOp<internal::scalar_sqrt_op<Scalar>, const Derived>

Public static functions

static auto Identity() -> const IdentityReturnType
static auto Identity(Index rows, Index cols) -> const IdentityReturnType
static auto Unit(Index size, Index i) -> const BasisReturnType
static auto Unit(Index i) -> const BasisReturnType
static auto UnitW() -> const BasisReturnType
static auto UnitX() -> const BasisReturnType
static auto UnitY() -> const BasisReturnType
static auto UnitZ() -> const BasisReturnType

Public functions

auto acosh() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic cosine use ArrayBase::acosh .
auto adjoint() const -> const AdjointReturnType
void adjointInPlace()
template<typename EssentialPart>
void applyHouseholderOnTheLeft(const EssentialPart& essential, const Scalar& tau, Scalar* workspace)
template<typename EssentialPart>
void applyHouseholderOnTheRight(const EssentialPart& essential, const Scalar& tau, Scalar* workspace)
template<typename OtherDerived>
void applyOnTheLeft(const EigenBase<OtherDerived>& other)
template<typename OtherScalar>
void applyOnTheLeft(Index p, Index q, const JacobiRotation<OtherScalar>& j)
template<typename OtherDerived>
void applyOnTheRight(const EigenBase<OtherDerived>& other)
auto array() -> ArrayWrapper<Derived>
auto array() const -> const ArrayWrapper<const Derived>
auto asDiagonal() const -> const DiagonalWrapper<const Derived>
auto asinh() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic sine use ArrayBase::asinh .
auto atanh() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic cosine use ArrayBase::atanh .
auto bdcSvd(unsigned int computationOptions = 0) const -> BDCSVD<PlainObject>
template<typename CustomBinaryOp, typename OtherDerived>
auto binaryExpr(const Eigen::MatrixBase<OtherDerived>& other, const CustomBinaryOp& func = CustomBinaryOp()) const -> const CwiseBinaryOp<CustomBinaryOp, const Derived, const OtherDerived>
auto blueNorm() const -> RealScalar
auto colPivHouseholderQr() const -> const ColPivHouseholderQR<PlainObject>
auto completeOrthogonalDecomposition() const -> const CompleteOrthogonalDecomposition<PlainObject>
template<typename ResultType>
void computeInverseAndDetWithCheck(ResultType& inverse, typename ResultType::Scalar& determinant, bool& invertible, const RealScalar& absDeterminantThreshold = NumTraits<Scalar>::dummy_precision()) const
template<typename ResultType>
void computeInverseWithCheck(ResultType& inverse, bool& invertible, const RealScalar& absDeterminantThreshold = NumTraits<Scalar>::dummy_precision()) const
auto cos() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise cosine use ArrayBase::cos .
auto cosh() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise hyperbolic cosine use ArrayBase::cosh .
auto cwiseAbs() const -> const CwiseAbsReturnType
auto cwiseAbs2() const -> const CwiseAbs2ReturnType
template<typename OtherDerived>
auto cwiseEqual(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<std::equal_to<Scalar>, const Derived, const OtherDerived>
auto cwiseEqual(const Scalar& s) const -> const CwiseScalarEqualReturnType
auto cwiseInverse() const -> const CwiseInverseReturnType
template<typename OtherDerived>
auto cwiseMax(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_max_op<Scalar, Scalar>, const Derived, const OtherDerived>
auto cwiseMax(const Scalar& other) const -> const CwiseBinaryOp<internal::scalar_max_op<Scalar, Scalar>, const Derived, const ConstantReturnType>
template<typename OtherDerived>
auto cwiseMin(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_min_op<Scalar, Scalar>, const Derived, const OtherDerived>
auto cwiseMin(const Scalar& other) const -> const CwiseBinaryOp<internal::scalar_min_op<Scalar, Scalar>, const Derived, const ConstantReturnType>
template<typename OtherDerived>
auto cwiseNotEqual(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<std::not_equal_to<Scalar>, const Derived, const OtherDerived>
template<typename OtherDerived>
auto cwiseProduct(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_product_op<Derived ::Scalar, OtherDerived ::Scalar>, const Derived, const OtherDerived>
template<typename OtherDerived>
auto cwiseQuotient(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_quotient_op<Scalar>, const Derived, const OtherDerived>
auto cwiseSign() const -> const CwiseSignReturnType
auto cwiseSqrt() const -> const CwiseSqrtReturnType
auto determinant() const -> Scalar
auto diagonal() -> DiagonalReturnType
auto diagonal() const -> ConstDiagonalReturnType
auto diagonal(Index index) -> DiagonalDynamicIndexReturnType
auto diagonal(Index index) const -> ConstDiagonalDynamicIndexReturnType
auto diagonalSize() const -> Index
template<typename OtherDerived>
auto dot(const MatrixBase<OtherDerived>& other) const -> ScalarBinaryOpTraits<typename internal::traits<Derived>::Scalar, typename internal::traits<OtherDerived>::Scalar>::ReturnType
auto eigenvalues() const -> EigenvaluesReturnType
Computes the eigenvalues of a matrix.
auto exp() const -> const MatrixExponentialReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise exponential use ArrayBase::exp .
auto forceAlignedAccess() const -> const Derived&
auto forceAlignedAccess() -> Derived&
template<bool Enable>
auto forceAlignedAccessIf() const -> internal::add_const_on_value_type<typename internal::conditional<Enable, ForceAlignedAccess<Derived>, Derived&>::type>::type
template<bool Enable>
auto forceAlignedAccessIf() -> internal::conditional<Enable, ForceAlignedAccess<Derived>, Derived&>::type
auto fullPivHouseholderQr() const -> const FullPivHouseholderQR<PlainObject>
auto fullPivLu() const -> const FullPivLU<PlainObject>
auto hnormalized() const -> const HNormalizedReturnType
homogeneous normalization
auto householderQr() const -> const HouseholderQR<PlainObject>
auto hypotNorm() const -> RealScalar
auto inverse() const -> const Inverse<Derived>
auto isDiagonal(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
auto isIdentity(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
auto isLowerTriangular(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
template<typename OtherDerived>
auto isOrthogonal(const MatrixBase<OtherDerived>& other, const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
auto isUnitary(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
auto isUpperTriangular(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const -> bool
auto jacobiSvd(unsigned int computationOptions = 0) const -> JacobiSVD<PlainObject>
template<typename OtherDerived>
auto lazyProduct(const MatrixBase<OtherDerived>& other) const -> const Product<Derived, OtherDerived, LazyProduct>
auto ldlt() const -> const LDLT<PlainObject>
auto llt() const -> const LLT<PlainObject>
auto log() const -> const MatrixLogarithmReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise logarithm use ArrayBase::log .
template<int p>
auto lpNorm() const -> RealScalar
auto lu() const -> const PartialPivLU<PlainObject>
template<typename EssentialPart>
void makeHouseholder(EssentialPart& essential, Scalar& tau, RealScalar& beta) const
void makeHouseholderInPlace(Scalar& tau, RealScalar& beta)
auto matrixFunction(StemFunction f) const -> const MatrixFunctionReturnValue<Derived>
Helper function for the unsupported MatrixFunctions module.
auto noalias() -> NoAlias<Derived, Eigen::MatrixBase>
auto norm() const -> RealScalar
void normalize()
auto normalized() const -> const PlainObject
template<typename OtherDerived>
auto operator&&(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_boolean_and_op, const Derived, const OtherDerived>
template<typename T>
auto operator*(const T& scalar) const -> const CwiseBinaryOp<internal::scalar_product_op<Scalar, T>, Derived, Constant<T>>
template<typename OtherDerived>
auto operator*(const MatrixBase<OtherDerived>& other) const -> const Product<Derived, OtherDerived>
template<typename DiagonalDerived>
auto operator*(const DiagonalBase<DiagonalDerived>& diagonal) const -> const Product<Derived, DiagonalDerived, LazyProduct>
template<typename OtherDerived>
auto operator*=(const EigenBase<OtherDerived>& other) -> Derived&
template<typename OtherDerived>
auto operator!=(const MatrixBase<OtherDerived>& other) const -> bool
template<typename OtherDerived>
auto operator+(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<sum<Scalar>, const Derived, const OtherDerived>
template<typename OtherDerived>
auto operator+=(const MatrixBase<OtherDerived>& other) -> Derived&
template<typename OtherDerived>
auto operator-(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<difference<Scalar>, const Derived, const OtherDerived>
template<typename OtherDerived>
auto operator-=(const MatrixBase<OtherDerived>& other) -> Derived&
template<typename T>
auto operator/(const T& scalar) const -> const CwiseBinaryOp<internal::scalar_quotient_op<Scalar, T>, Derived, Constant<T>>
auto operator=(const MatrixBase& other) -> Derived&
template<typename OtherDerived>
auto operator==(const MatrixBase<OtherDerived>& other) const -> bool
auto operatorNorm() const -> RealScalar
Computes the L2 operator norm.
template<typename OtherDerived>
auto operator||(const Eigen::MatrixBase<OtherDerived>& other) const -> const CwiseBinaryOp<internal::scalar_boolean_or_op, const Derived, const OtherDerived>
auto partialPivLu() const -> const PartialPivLU<PlainObject>
auto pow(const RealScalar& p) const -> const MatrixPowerReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise power to p use ArrayBase::pow .
auto pow(const std::complex<RealScalar>& p) const -> const MatrixComplexPowerReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise power to p use ArrayBase::pow .
template<unsigned int UpLo>
auto selfadjointView() const -> MatrixBase<Derived>::template ConstSelfAdjointViewReturnType<UpLo>::Type
template<unsigned int UpLo>
auto selfadjointView() -> MatrixBase<Derived>::template SelfAdjointViewReturnType<UpLo>::Type
auto setIdentity() -> Derived&
auto setIdentity(Index rows, Index cols) -> Derived&
Resizes to the given size, and writes the identity expression (not necessarily square) into *this.
auto setUnit(Index i) -> Derived&
Set the coefficients of *this to the i-th unit (basis) vector.
auto setUnit(Index newSize, Index i) -> Derived&
Resizes to the given newSize, and writes the i-th unit (basis) vector into *this.
auto sin() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise sine use ArrayBase::sin .
auto sinh() const -> const MatrixFunctionReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise hyperbolic sine use ArrayBase::sinh .
auto sqrt() const -> const MatrixSquareRootReturnValue<Derived>
This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise square root use ArrayBase::sqrt .
auto squaredNorm() const -> RealScalar
auto stableNorm() const -> RealScalar
void stableNormalize()
auto stableNormalized() const -> const PlainObject
auto trace() const -> Scalar
template<unsigned int Mode>
auto triangularView() -> MatrixBase<Derived>::template TriangularViewReturnType<Mode>::Type
template<unsigned int Mode>
auto triangularView() const -> MatrixBase<Derived>::template ConstTriangularViewReturnType<Mode>::Type

Friends

template<typename T>
auto operator*(const T& scalar, const StorageBaseType& expr) -> const CwiseBinaryOp<internal::scalar_product_op<T, Scalar>, Constant<T>, Derived>

Typedef documentation

template<typename Derived>
typedef CwiseUnaryOp<internal::scalar_abs2_op<Scalar>, const Derived> Eigen::MatrixBase<Derived>::CwiseAbs2ReturnType

template<typename Derived>
typedef CwiseUnaryOp<internal::scalar_abs_op<Scalar>, const Derived> Eigen::MatrixBase<Derived>::CwiseAbsReturnType

template<typename Derived>
typedef CwiseUnaryOp<internal::scalar_inverse_op<Scalar>, const Derived> Eigen::MatrixBase<Derived>::CwiseInverseReturnType

template<typename Derived>
typedef CwiseBinaryOp<internal::scalar_cmp_op<Scalar, Scalar, internal::cmp_EQ>, const Derived, const ConstantReturnType> Eigen::MatrixBase<Derived>::CwiseScalarEqualReturnType

template<typename Derived>
typedef CwiseUnaryOp<internal::scalar_sign_op<Scalar>, const Derived> Eigen::MatrixBase<Derived>::CwiseSignReturnType

template<typename Derived>
typedef CwiseUnaryOp<internal::scalar_sqrt_op<Scalar>, const Derived> Eigen::MatrixBase<Derived>::CwiseSqrtReturnType

Function documentation

template<typename Derived>
static const IdentityReturnType Eigen::MatrixBase<Derived>::Identity()

Returns an expression of the identity matrix (not necessarily square).

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

Example:

cout << Matrix<double, 3, 4>::Identity() << endl;

Output:

1 0 0 0
0 1 0 0
0 0 1 0

template<typename Derived>
static const IdentityReturnType Eigen::MatrixBase<Derived>::Identity(Index rows, Index cols)

Returns an expression of the identity matrix (not necessarily square).

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 Identity() should be used instead.

Example:

cout << MatrixXd::Identity(4, 3) << endl;

Output:

1 0 0
0 1 0
0 0 1
0 0 0

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::Unit(Index size, Index i)

Returns an expression of the i-th unit (basis) vector.

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.

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::Unit(Index i)

Returns an expression of the i-th unit (basis) vector.

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 for fixed-size vector only.

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::UnitW()

Returns an expression of the W axis unit vector (0,0,0,1)

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.

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::UnitX()

Returns an expression of the X axis unit vector (1{,0}^*)

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.

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::UnitY()

Returns an expression of the Y axis unit vector (0,1{,0}^*)

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.

template<typename Derived>
static const BasisReturnType Eigen::MatrixBase<Derived>::UnitZ()

Returns an expression of the Z axis unit vector (0,0,1{,0}^*)

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.

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::acosh() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic cosine use ArrayBase::acosh .

Returns an expression of the matrix inverse hyperbolic cosine of *this.

template<typename Derived>
const AdjointReturnType Eigen::MatrixBase<Derived>::adjoint() const

Returns an expression of the adjoint (i.e. conjugate transpose) of *this.

Example:

Matrix2cf m = Matrix2cf::Random();
cout << "Here is the 2x2 complex matrix m:" << endl << m << endl;
cout << "Here is the adjoint of m:" << endl << m.adjoint() << endl;

Output:

Here is the 2x2 complex matrix m:
 (-0.211,0.68) (-0.605,0.823)
 (0.597,0.566)  (0.536,-0.33)
Here is the adjoint of m:
 (-0.211,-0.68)  (0.597,-0.566)
(-0.605,-0.823)    (0.536,0.33)

template<typename Derived>
void Eigen::MatrixBase<Derived>::adjointInPlace()

This is the "in place" version of adjoint(): it replaces *this by its own transpose. Thus, doing m.adjointInPlace(); has the same effect on m as doing m = m.adjoint().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 adjoint. If you just need the adjoint of a matrix, use adjoint().

template<typename Derived> template<typename EssentialPart>
void Eigen::MatrixBase<Derived>::applyHouseholderOnTheLeft(const EssentialPart& essential, const Scalar& tau, Scalar* workspace)

Parameters
essential the essential part of the vector v
tau the scaling factor of the Householder transformation
workspace a pointer to working space with at least this->cols() entries

Apply the elementary reflector H given by $ H = I - tau v v^*$ with $ v^T = [1 essential^T] $ from the left to a vector or matrix.

On input:

template<typename Derived> template<typename EssentialPart>
void Eigen::MatrixBase<Derived>::applyHouseholderOnTheRight(const EssentialPart& essential, const Scalar& tau, Scalar* workspace)

Parameters
essential the essential part of the vector v
tau the scaling factor of the Householder transformation
workspace a pointer to working space with at least this->rows() entries

Apply the elementary reflector H given by $ H = I - tau v v^*$ with $ v^T = [1 essential^T] $ from the right to a vector or matrix.

On input:

template<typename Derived> template<typename OtherDerived>
void Eigen::MatrixBase<Derived>::applyOnTheLeft(const EigenBase<OtherDerived>& other)

replaces *this by other * *this.

Example:

Matrix3f A = Matrix3f::Random(3,3), B;
B << 0,1,0,  
     0,0,1,  
     1,0,0;
cout << "At start, A = " << endl << A << endl;
A.applyOnTheLeft(B); 
cout << "After applyOnTheLeft, A = " << endl << A << endl;

Output:

At start, A = 
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
After applyOnTheLeft, A = 
-0.211  0.823  0.536
 0.566 -0.605 -0.444
  0.68  0.597  -0.33

template<typename Derived> template<typename OtherScalar>
void Eigen::MatrixBase<Derived>::applyOnTheLeft(Index p, Index q, const JacobiRotation<OtherScalar>& j)

This is defined in the Jacobi module. #include <Eigen/Jacobi> Applies the rotation in the plane j to the rows p and q of *this, i.e., it computes B = J * B, with $ B = \left ( \begin{array}{cc} \text{*this.row}(p) \\ \text{*this.row}(q) \end{array} \right ) $ .

template<typename Derived> template<typename OtherDerived>
void Eigen::MatrixBase<Derived>::applyOnTheRight(const EigenBase<OtherDerived>& other)

replaces *this by *this * other. It is equivalent to MatrixBase::operator*=().

Example:

Matrix3f A = Matrix3f::Random(3,3), B;
B << 0,1,0,  
     0,0,1,  
     1,0,0;
cout << "At start, A = " << endl << A << endl;
A *= B;
cout << "After A *= B, A = " << endl << A << endl;
A.applyOnTheRight(B);  // equivalent to A *= B
cout << "After applyOnTheRight, A = " << endl << A << endl;

Output:

At start, A = 
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
After A *= B, A = 
 -0.33   0.68  0.597
 0.536 -0.211  0.823
-0.444  0.566 -0.605
After applyOnTheRight, A = 
 0.597  -0.33   0.68
 0.823  0.536 -0.211
-0.605 -0.444  0.566

template<typename Derived>
ArrayWrapper<Derived> Eigen::MatrixBase<Derived>::array()

Returns an Array expression of this matrix

template<typename Derived>
const ArrayWrapper<const Derived> Eigen::MatrixBase<Derived>::array() const

Returns a const Array expression of this matrix

template<typename Derived>
const DiagonalWrapper<const Derived> Eigen::MatrixBase<Derived>::asDiagonal() const

Returns a pseudo-expression of a diagonal matrix with *this as vector of diagonal coefficients

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 << Matrix3i(Vector3i(2,5,6).asDiagonal()) << endl;

Output:

2 0 0
0 5 0
0 0 6

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::asinh() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic sine use ArrayBase::asinh .

Returns an expression of the matrix inverse hyperbolic sine of *this.

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::atanh() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise inverse hyperbolic cosine use ArrayBase::atanh .

Returns an expression of the matrix inverse hyperbolic cosine of *this.

template<typename Derived>
BDCSVD<PlainObject> Eigen::MatrixBase<Derived>::bdcSvd(unsigned int computationOptions = 0) const

Returns the singular value decomposition of *this computed by Divide & Conquer algorithm

This is defined in the SVD module. #include <Eigen/SVD>

template<typename Derived> template<typename CustomBinaryOp, typename OtherDerived>
const CwiseBinaryOp<CustomBinaryOp, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::binaryExpr(const Eigen::MatrixBase<OtherDerived>& other, const CustomBinaryOp& func = CustomBinaryOp()) const

Returns an expression of a custom coefficient-wise operator func of *this and other

The template parameter CustomBinaryOp is the type of the functor of the custom operator (see class CwiseBinaryOp for an example)

Here is an example illustrating the use of custom functors:

#include <Eigen/Core>
#include <iostream>
using namespace Eigen;
using namespace std;

// define a custom template binary functor
template<typename Scalar> struct MakeComplexOp {
  EIGEN_EMPTY_STRUCT_CTOR(MakeComplexOp)
  typedef complex<Scalar> result_type;
  complex<Scalar> operator()(const Scalar& a, const Scalar& b) const { return complex<Scalar>(a,b); }
};

int main(int, char**)
{
  Matrix4d m1 = Matrix4d::Random(), m2 = Matrix4d::Random();
  cout << m1.binaryExpr(m2, MakeComplexOp<double>()) << endl;
  return 0;
}

Output:

   (0.68,0.271)  (0.823,-0.967) (-0.444,-0.687)   (-0.27,0.998)
 (-0.211,0.435) (-0.605,-0.514)  (0.108,-0.198) (0.0268,-0.563)
 (0.566,-0.717)  (-0.33,-0.726) (-0.0452,-0.74)  (0.904,0.0259)
  (0.597,0.214)   (0.536,0.608)  (0.258,-0.782)   (0.832,0.678)

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::blueNorm() const

Returns the l2 norm of *this using the Blue's algorithm. A Portable Fortran Program to Find the Euclidean Norm of a Vector, ACM TOMS, Vol 4, Issue 1, 1978.

For architecture/scalar types without vectorization, this version is much faster than stableNorm(). Otherwise the stableNorm() is faster.

template<typename Derived>
const ColPivHouseholderQR<PlainObject> Eigen::MatrixBase<Derived>::colPivHouseholderQr() const

Returns the column-pivoting Householder QR decomposition of *this.

template<typename Derived>
const CompleteOrthogonalDecomposition<PlainObject> Eigen::MatrixBase<Derived>::completeOrthogonalDecomposition() const

Returns the complete orthogonal decomposition of *this.

template<typename Derived> template<typename ResultType>
void Eigen::MatrixBase<Derived>::computeInverseAndDetWithCheck(ResultType& inverse, typename ResultType::Scalar& determinant, bool& invertible, const RealScalar& absDeterminantThreshold = NumTraits<Scalar>::dummy_precision()) const

Parameters
inverse Reference to the matrix in which to store the inverse.
determinant Reference to the variable in which to store the determinant.
invertible Reference to the bool variable in which to store whether the matrix is invertible.
absDeterminantThreshold Optional parameter controlling the invertibility check. The matrix will be declared invertible if the absolute value of its determinant is greater than this threshold.

This is defined in the LU module. #include <Eigen/LU>

Computation of matrix inverse and determinant, with invertibility check.

This is only for fixed-size square matrices of size up to 4x4.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
Matrix3d inverse;
bool invertible;
double determinant;
m.computeInverseAndDetWithCheck(inverse,determinant,invertible);
cout << "Its determinant is " << determinant << endl;
if(invertible) {
  cout << "It is invertible, and its inverse is:" << endl << inverse << endl;
}
else {
  cout << "It is not invertible." << 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
Its determinant is 0.209
It is invertible, and its inverse is:
-0.199   2.23   2.84
  1.01 -0.555  -1.42
 -1.62   3.59   3.29

template<typename Derived> template<typename ResultType>
void Eigen::MatrixBase<Derived>::computeInverseWithCheck(ResultType& inverse, bool& invertible, const RealScalar& absDeterminantThreshold = NumTraits<Scalar>::dummy_precision()) const

Parameters
inverse Reference to the matrix in which to store the inverse.
invertible Reference to the bool variable in which to store whether the matrix is invertible.
absDeterminantThreshold Optional parameter controlling the invertibility check. The matrix will be declared invertible if the absolute value of its determinant is greater than this threshold.

This is defined in the LU module. #include <Eigen/LU>

Computation of matrix inverse, with invertibility check.

This is only for fixed-size square matrices of size up to 4x4.

Example:

Matrix3d m = Matrix3d::Random();
cout << "Here is the matrix m:" << endl << m << endl;
Matrix3d inverse;
bool invertible;
m.computeInverseWithCheck(inverse,invertible);
if(invertible) {
  cout << "It is invertible, and its inverse is:" << endl << inverse << endl;
}
else {
  cout << "It is not invertible." << 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
It is invertible, and its inverse is:
-0.199   2.23   2.84
  1.01 -0.555  -1.42
 -1.62   3.59   3.29

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::cos() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise cosine use ArrayBase::cos .

Returns an expression of the matrix cosine of *this.

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::cosh() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise hyperbolic cosine use ArrayBase::cosh .

Returns an expression of the matrix hyperbolic cosine of *this.

template<typename Derived>
const CwiseAbsReturnType Eigen::MatrixBase<Derived>::cwiseAbs() const

Returns an expression of the coefficient-wise absolute value of *this

Example:

MatrixXd m(2,3);
m << 2, -4, 6,   
     -5, 1, 0;
cout << m.cwiseAbs() << endl;

Output:

 

cwiseAbs2()

template<typename Derived>
const CwiseAbs2ReturnType Eigen::MatrixBase<Derived>::cwiseAbs2() const

Returns an expression of the coefficient-wise squared absolute value of *this

Example:

MatrixXd m(2,3);
m << 2, -4, 6,   
     -5, 1, 0;
cout << m.cwiseAbs2() << endl;

Output:

 

cwiseAbs()

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<std::equal_to<Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseEqual(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise == operator of *this and other

Example:

MatrixXi m(2,2);
m << 1, 0,
     1, 1;
cout << "Comparing m with identity matrix:" << endl;
cout << m.cwiseEqual(MatrixXi::Identity(2,2)) << endl;
Index count = m.cwiseEqual(MatrixXi::Identity(2,2)).count();
cout << "Number of coefficients that are equal: " << count << endl;

Output:

Comparing m with identity matrix:
1 1
0 1
Number of coefficients that are equal: 3

template<typename Derived>
const CwiseScalarEqualReturnType Eigen::MatrixBase<Derived>::cwiseEqual(const Scalar& s) const

Returns an expression of the coefficient-wise == operator of *this and a scalar s

template<typename Derived>
const CwiseInverseReturnType Eigen::MatrixBase<Derived>::cwiseInverse() const

Returns an expression of the coefficient-wise inverse of *this.

Example:

MatrixXd m(2,3);
m << 2, 0.5, 1,   
     3, 0.25, 1;
cout << m.cwiseInverse() << endl;

Output:

 

cwiseProduct()

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_max_op<Scalar, Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseMax(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise max of *this and other

Example:

Vector3d v(2,3,4), w(4,2,3);
cout << v.cwiseMax(w) << endl;

Output:

4
3
4

template<typename Derived>
const CwiseBinaryOp<internal::scalar_max_op<Scalar, Scalar>, const Derived, const ConstantReturnType> Eigen::MatrixBase<Derived>::cwiseMax(const Scalar& other) const

Returns an expression of the coefficient-wise max of *this and scalar other

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_min_op<Scalar, Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseMin(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise min of *this and other

Example:

Vector3d v(2,3,4), w(4,2,3);
cout << v.cwiseMin(w) << endl;

Output:

2
2
3

template<typename Derived>
const CwiseBinaryOp<internal::scalar_min_op<Scalar, Scalar>, const Derived, const ConstantReturnType> Eigen::MatrixBase<Derived>::cwiseMin(const Scalar& other) const

Returns an expression of the coefficient-wise min of *this and scalar other

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<std::not_equal_to<Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseNotEqual(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise != operator of *this and other

Example:

MatrixXi m(2,2);
m << 1, 0,
     1, 1;
cout << "Comparing m with identity matrix:" << endl;
cout << m.cwiseNotEqual(MatrixXi::Identity(2,2)) << endl;
Index count = m.cwiseNotEqual(MatrixXi::Identity(2,2)).count();
cout << "Number of coefficients that are not equal: " << count << endl;

Output:

Comparing m with identity matrix:
0 0
1 0
Number of coefficients that are not equal: 1

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_product_op<Derived ::Scalar, OtherDerived ::Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseProduct(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the Schur product (coefficient wise product) of *this and other

Example:

Matrix3i a = Matrix3i::Random(), b = Matrix3i::Random();
Matrix3i c = a.cwiseProduct(b);
cout << "a:\n" << a << "\nb:\n" << b << "\nc:\n" << c << endl;

Output:

a:
 7  6 -3
-2  9  6
 6 -6 -5
b:
 1 -3  9
 0  0  3
 3  9  5
c:
  7 -18 -27
  0   0  18
 18 -54 -25

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_quotient_op<Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::cwiseQuotient(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise quotient of *this and other

Example:

Vector3d v(2,3,4), w(4,2,3);
cout << v.cwiseQuotient(w) << endl;

Output:

 0.5
 1.5
1.33

template<typename Derived>
const CwiseSignReturnType Eigen::MatrixBase<Derived>::cwiseSign() const

Returns an expression of the coefficient-wise signum of *this.

Example:

MatrixXd m(2,3);
m <<  2, -4, 6,
     -5,  1, 0;
cout << m.cwiseSign() << endl;

Output:

 1 -1  1
-1  1  0

template<typename Derived>
const CwiseSqrtReturnType Eigen::MatrixBase<Derived>::cwiseSqrt() const

Returns an expression of the coefficient-wise square root of *this.

Example:

Vector3d v(1,2,4);
cout << v.cwiseSqrt() << endl;

Output:

cwisePow(), cwiseSquare()

template<typename Derived>
Scalar Eigen::MatrixBase<Derived>::determinant() const

Returns the determinant of this matrix

This is defined in the LU module. #include <Eigen/LU>

template<typename Derived>
DiagonalReturnType Eigen::MatrixBase<Derived>::diagonal()

Returns an expression of the main diagonal of the matrix *this

*this is not required to be square.

Example:

Matrix3i m = Matrix3i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here are the coefficients on the main diagonal of m:" << endl
     << m.diagonal() << endl;

Output:

Here is the matrix m:
 7  6 -3
-2  9  6
 6 -6 -5
Here are the coefficients on the main diagonal of m:
 7
 9
-5

*this is not required to be square.

The template parameter DiagIndex represent a super diagonal if DiagIndex > 0 and a sub diagonal otherwise. DiagIndex == 0 is equivalent to the main diagonal.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here are the coefficients on the 1st super-diagonal and 2nd sub-diagonal of m:" << endl
     << m.diagonal<1>().transpose() << endl
     << m.diagonal<-2>().transpose() << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here are the coefficients on the 1st super-diagonal and 2nd sub-diagonal of m:
9 1 9
6 6

template<typename Derived>
ConstDiagonalReturnType Eigen::MatrixBase<Derived>::diagonal() const

This is the const version of diagonal().

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

template<typename Derived>
DiagonalDynamicIndexReturnType Eigen::MatrixBase<Derived>::diagonal(Index index)

Returns an expression of the DiagIndex-th sub or super diagonal of the matrix *this

*this is not required to be square.

The template parameter DiagIndex represent a super diagonal if DiagIndex > 0 and a sub diagonal otherwise. DiagIndex == 0 is equivalent to the main diagonal.

Example:

Matrix4i m = Matrix4i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here are the coefficients on the 1st super-diagonal and 2nd sub-diagonal of m:" << endl
     << m.diagonal(1).transpose() << endl
     << m.diagonal(-2).transpose() << endl;

Output:

Here is the matrix m:
 7  9 -5 -3
-2 -6  1  0
 6 -3  0  9
 6  6  3  9
Here are the coefficients on the 1st super-diagonal and 2nd sub-diagonal of m:
9 1 9
6 6

template<typename Derived>
ConstDiagonalDynamicIndexReturnType Eigen::MatrixBase<Derived>::diagonal(Index index) const

This is the const version of diagonal(Index).

template<typename Derived>
Index Eigen::MatrixBase<Derived>::diagonalSize() const

Returns the size of the main diagonal, which is min(rows(),cols()).

template<typename Derived> template<typename OtherDerived>
ScalarBinaryOpTraits<typename internal::traits<Derived>::Scalar, typename internal::traits<OtherDerived>::Scalar>::ReturnType Eigen::MatrixBase<Derived>::dot(const MatrixBase<OtherDerived>& other) const

Returns the dot product of *this with other.

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.

template<typename Derived>
EigenvaluesReturnType Eigen::MatrixBase<Derived>::eigenvalues() const

Computes the eigenvalues of a matrix.

Returns Column vector containing the eigenvalues.

This is defined in the Eigenvalues module. #include <Eigen/Eigenvalues> This function computes the eigenvalues with the help of the EigenSolver class (for real matrices) or the ComplexEigenSolver class (for complex matrices).

The eigenvalues are repeated according to their algebraic multiplicity, so there are as many eigenvalues as rows in the matrix.

The SelfAdjointView class provides a better algorithm for selfadjoint matrices.

Example:

MatrixXd ones = MatrixXd::Ones(3,3);
VectorXcd eivals = ones.eigenvalues();
cout << "The eigenvalues of the 3x3 matrix of ones are:" << endl << eivals << endl;

Output:

The eigenvalues of the 3x3 matrix of ones are:
(-5.31e-17,0)
        (3,0)
        (0,0)

template<typename Derived>
const MatrixExponentialReturnValue<Derived> Eigen::MatrixBase<Derived>::exp() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise exponential use ArrayBase::exp .

Returns an expression of the matrix exponential of *this.

template<typename Derived>
const Derived& Eigen::MatrixBase<Derived>::forceAlignedAccess() const

Returns an expression of *this with forced aligned access

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::forceAlignedAccess()

Returns an expression of *this with forced aligned access

template<typename Derived> template<bool Enable>
internal::add_const_on_value_type<typename internal::conditional<Enable, ForceAlignedAccess<Derived>, Derived&>::type>::type Eigen::MatrixBase<Derived>::forceAlignedAccessIf() const

Returns an expression of *this with forced aligned access if Enable is true.

template<typename Derived> template<bool Enable>
internal::conditional<Enable, ForceAlignedAccess<Derived>, Derived&>::type Eigen::MatrixBase<Derived>::forceAlignedAccessIf()

Returns an expression of *this with forced aligned access if Enable is true.

template<typename Derived>
const FullPivHouseholderQR<PlainObject> Eigen::MatrixBase<Derived>::fullPivHouseholderQr() const

Returns the full-pivoting Householder QR decomposition of *this.

template<typename Derived>
const FullPivLU<PlainObject> Eigen::MatrixBase<Derived>::fullPivLu() const

Returns the full-pivoting LU decomposition of *this.

This is defined in the LU module. #include <Eigen/LU>

template<typename Derived>
const HouseholderQR<PlainObject> Eigen::MatrixBase<Derived>::householderQr() const

Returns the Householder QR decomposition of *this.

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::hypotNorm() const

Returns the l2 norm of *this avoiding undeflow and overflow. This version use a concatenation of hypot() calls, and it is very slow.

template<typename Derived>
const Inverse<Derived> Eigen::MatrixBase<Derived>::inverse() const

Returns the matrix inverse of this matrix.

This is defined in the LU module. #include <Eigen/LU>

For small fixed sizes up to 4x4, this method uses cofactors. In the general case, this method uses class PartialPivLU.

template<typename Derived>
bool Eigen::MatrixBase<Derived>::isDiagonal(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately equal to a diagonal matrix, within the precision given by prec.

Example:

Matrix3d m = 10000 * Matrix3d::Identity();
m(0,2) = 1;
cout << "Here's the matrix m:" << endl << m << endl;
cout << "m.isDiagonal() returns: " << m.isDiagonal() << endl;
cout << "m.isDiagonal(1e-3) returns: " << m.isDiagonal(1e-3) << endl;

Output:

Here's the matrix m:
1e+04     0     1
    0 1e+04     0
    0     0 1e+04
m.isDiagonal() returns: 0
m.isDiagonal(1e-3) returns: 1

template<typename Derived>
bool Eigen::MatrixBase<Derived>::isIdentity(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately equal to the identity matrix (not necessarily square), within the precision given by prec.

Example:

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

Output:

Here's the matrix m:
     1      0 0.0001
     0      1      0
     0      0      1
m.isIdentity() returns: 0
m.isIdentity(1e-3) returns: 1

template<typename Derived>
bool Eigen::MatrixBase<Derived>::isLowerTriangular(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately equal to a lower triangular matrix, within the precision given by prec.

template<typename Derived> template<typename OtherDerived>
bool Eigen::MatrixBase<Derived>::isOrthogonal(const MatrixBase<OtherDerived>& other, const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately orthogonal to other, within the precision given by prec.

Example:

Vector3d v(1,0,0);
Vector3d w(1e-4,0,1);
cout << "Here's the vector v:" << endl << v << endl;
cout << "Here's the vector w:" << endl << w << endl;
cout << "v.isOrthogonal(w) returns: " << v.isOrthogonal(w) << endl;
cout << "v.isOrthogonal(w,1e-3) returns: " << v.isOrthogonal(w,1e-3) << endl;

Output:

Here's the vector v:
1
0
0
Here's the vector w:
0.0001
     0
     1
v.isOrthogonal(w) returns: 0
v.isOrthogonal(w,1e-3) returns: 1

template<typename Derived>
bool Eigen::MatrixBase<Derived>::isUnitary(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately an unitary matrix, within the precision given by prec. In the case where the Scalar type is real numbers, a unitary matrix is an orthogonal matrix, whence the name.

Example:

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

Output:

Here's the matrix m:
     1      0 0.0001
     0      1      0
     0      0      1
m.isUnitary() returns: 0
m.isUnitary(1e-3) returns: 1

template<typename Derived>
bool Eigen::MatrixBase<Derived>::isUpperTriangular(const RealScalar& prec = NumTraits<Scalar>::dummy_precision()) const

Returns true if *this is approximately equal to an upper triangular matrix, within the precision given by prec.

template<typename Derived>
JacobiSVD<PlainObject> Eigen::MatrixBase<Derived>::jacobiSvd(unsigned int computationOptions = 0) const

Returns the singular value decomposition of *this computed by two-sided Jacobi transformations.

This is defined in the SVD module. #include <Eigen/SVD>

template<typename Derived> template<typename OtherDerived>
const Product<Derived, OtherDerived, LazyProduct> Eigen::MatrixBase<Derived>::lazyProduct(const MatrixBase<OtherDerived>& other) const

Returns an expression of the matrix product of *this and other without implicit evaluation.

The returned product will behave like any other expressions: the coefficients of the product will be computed once at a time as requested. This might be useful in some extremely rare cases when only a small and no coherent fraction of the result's coefficients have to be computed.

template<typename Derived>
const LDLT<PlainObject> Eigen::MatrixBase<Derived>::ldlt() const

Returns the Cholesky decomposition with full pivoting without square root of *this

This is defined in the Cholesky module. #include <Eigen/Cholesky>

template<typename Derived>
const LLT<PlainObject> Eigen::MatrixBase<Derived>::llt() const

Returns the LLT decomposition of *this

This is defined in the Cholesky module. #include <Eigen/Cholesky>

template<typename Derived>
const MatrixLogarithmReturnValue<Derived> Eigen::MatrixBase<Derived>::log() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise logarithm use ArrayBase::log .

Returns an expression of the matrix logarithm of *this.

template<typename Derived> template<int p>
RealScalar Eigen::MatrixBase<Derived>::lpNorm() const

Returns the coefficient-wise $ \ell^p $ norm of *this, that is, returns the p-th root of the sum of the p-th powers of the absolute values of the coefficients of *this. If p is the special value Eigen::Infinity, this function returns the $ \ell^\infty $ norm, that is the maximum of the absolute values of the coefficients of *this.

In all cases, if *this is empty, then the value 0 is returned.

template<typename Derived>
const PartialPivLU<PlainObject> Eigen::MatrixBase<Derived>::lu() const

Returns the partial-pivoting LU decomposition of *this.

This is defined in the LU module. #include <Eigen/LU>

Synonym of partialPivLu().

template<typename Derived> template<typename EssentialPart>
void Eigen::MatrixBase<Derived>::makeHouseholder(EssentialPart& essential, Scalar& tau, RealScalar& beta) const

Parameters
essential the essential part of the vector v
tau the scaling factor of the Householder transformation
beta the result of H * *this

Computes the elementary reflector H such that: $ H *this = [ beta 0 ... 0]^T $ where the transformation H is: $ H = I - tau v v^*$ and the vector v is: $ v^T = [1 essential^T] $

On output:

template<typename Derived>
void Eigen::MatrixBase<Derived>::makeHouseholderInPlace(Scalar& tau, RealScalar& beta)

Parameters
tau the scaling factor of the Householder transformation
beta the result of H * *this

Computes the elementary reflector H such that: $ H *this = [ beta 0 ... 0]^T $ where the transformation H is: $ H = I - tau v v^*$ and the vector v is: $ v^T = [1 essential^T] $

The essential part of the vector v is stored in *this.

On output:

template<typename Derived>
NoAlias<Derived, Eigen::MatrixBase> Eigen::MatrixBase<Derived>::noalias()

Returns a pseudo expression of *this with an operator= assuming no aliasing between *this and the source expression.

More precisely, noalias() allows to bypass the EvalBeforeAssignBit flag. Currently, even though several expressions may alias, only product expressions have this flag. Therefore, noalias() is only useful when the source expression contains a matrix product.

Here are some examples where noalias is useful:

D.noalias()  = A * B;
D.noalias() += A.transpose() * B;
D.noalias() -= 2 * A * B.adjoint();

On the other hand the following example will lead to a wrong result: A.noalias() = A * B; because the result matrix A is also an operand of the matrix product. Therefore, there is no alternative than evaluating A * B in a temporary, that is the default behavior when you write: A = A * B;

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::norm() const

Returns , for vectors, the l2 norm of *this, and for matrices the Frobenius norm. In both cases, it consists in the square root of the sum of the square of all the matrix entries. For vectors, this is also equals to the square root of the dot product of *this with itself.

template<typename Derived>
void Eigen::MatrixBase<Derived>::normalize()

Normalizes the vector, i.e. divides it by its own norm.

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.

template<typename Derived>
const PlainObject Eigen::MatrixBase<Derived>::normalized() const

Returns an expression of the quotient of *this by its own norm.

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.

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_boolean_and_op, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::operator&&(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise boolean and operator of *this and other

Example:

Array3d v(-1,2,1), w(-3,2,3);
cout << ((v<w) && (v<0)) << endl;

Output:

0
0
0

template<typename Derived> template<typename T>
const CwiseBinaryOp<internal::scalar_product_op<Scalar, T>, Derived, Constant<T>> Eigen::MatrixBase<Derived>::operator*(const T& scalar) const

Template parameters
T is the scalar type of scalar. It must be compatible with the scalar type of the given expression.
Returns an expression of *this scaled by the scalar factor scalar

template<typename Derived> template<typename OtherDerived>
const Product<Derived, OtherDerived> Eigen::MatrixBase<Derived>::operator*(const MatrixBase<OtherDerived>& other) const

Returns the matrix product of *this and other.

template<typename Derived> template<typename DiagonalDerived>
const Product<Derived, DiagonalDerived, LazyProduct> Eigen::MatrixBase<Derived>::operator*(const DiagonalBase<DiagonalDerived>& diagonal) const

Returns the diagonal matrix product of *this by the diagonal matrix diagonal.

template<typename Derived> template<typename OtherDerived>
Derived& Eigen::MatrixBase<Derived>::operator*=(const EigenBase<OtherDerived>& other)

Returns a reference to *this

replaces *this by *this * other.

Example:

Matrix3f A = Matrix3f::Random(3,3), B;
B << 0,1,0,  
     0,0,1,  
     1,0,0;
cout << "At start, A = " << endl << A << endl;
A *= B;
cout << "After A *= B, A = " << endl << A << endl;
A.applyOnTheRight(B);  // equivalent to A *= B
cout << "After applyOnTheRight, A = " << endl << A << endl;

Output:

At start, A = 
  0.68  0.597  -0.33
-0.211  0.823  0.536
 0.566 -0.605 -0.444
After A *= B, A = 
 -0.33   0.68  0.597
 0.536 -0.211  0.823
-0.444  0.566 -0.605
After applyOnTheRight, A = 
 0.597  -0.33   0.68
 0.823  0.536 -0.211
-0.605 -0.444  0.566

template<typename Derived> template<typename OtherDerived>
bool Eigen::MatrixBase<Derived>::operator!=(const MatrixBase<OtherDerived>& other) const

Returns true if at least one pair of coefficients of *this and other are not exactly equal to each other.

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<sum<Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::operator+(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the sum of *this and other

template<typename Derived> template<typename OtherDerived>
Derived& Eigen::MatrixBase<Derived>::operator+=(const MatrixBase<OtherDerived>& other)

Returns a reference to *this

replaces *this by *this + other.

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<difference<Scalar>, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::operator-(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the difference of *this and other

template<typename Derived> template<typename OtherDerived>
Derived& Eigen::MatrixBase<Derived>::operator-=(const MatrixBase<OtherDerived>& other)

Returns a reference to *this

replaces *this by *this - other.

template<typename Derived> template<typename T>
const CwiseBinaryOp<internal::scalar_quotient_op<Scalar, T>, Derived, Constant<T>> Eigen::MatrixBase<Derived>::operator/(const T& scalar) const

Template parameters
T is the scalar type of scalar. It must be compatible with the scalar type of the given expression.
Returns an expression of *this divided by the scalar value scalar

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::operator=(const MatrixBase& other)

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

template<typename Derived> template<typename OtherDerived>
bool Eigen::MatrixBase<Derived>::operator==(const MatrixBase<OtherDerived>& other) const

Returns true if each coefficients of *this and other are all exactly equal.

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::operatorNorm() const

Computes the L2 operator norm.

Returns Operator norm of the matrix.

This is defined in the Eigenvalues module. #include <Eigen/Eigenvalues> This function computes the L2 operator norm of a matrix, which is also known as the spectral norm. The norm of a matrix $ A $ is defined to be

\[ \|A\|_2 = \max_x \frac{\|Ax\|_2}{\|x\|_2} \]

where the maximum is over all vectors and the norm on the right is the Euclidean vector norm. The norm equals the largest singular value, which is the square root of the largest eigenvalue of the positive semi-definite matrix $ A^*A $ .

The current implementation uses the eigenvalues of $ A^*A $ , as computed by SelfAdjointView::eigenvalues(), to compute the operator norm of a matrix. The SelfAdjointView class provides a better algorithm for selfadjoint matrices.

Example:

MatrixXd ones = MatrixXd::Ones(3,3);
cout << "The operator norm of the 3x3 matrix of ones is "
     << ones.operatorNorm() << endl;

Output:

The operator norm of the 3x3 matrix of ones is 3

template<typename Derived> template<typename OtherDerived>
const CwiseBinaryOp<internal::scalar_boolean_or_op, const Derived, const OtherDerived> Eigen::MatrixBase<Derived>::operator||(const Eigen::MatrixBase<OtherDerived>& other) const

Returns an expression of the coefficient-wise boolean or operator of *this and other

Example:

Array3d v(-1,2,1), w(-3,2,3);
cout << ((v<w) || (v<0)) << endl;

Output:

1
0
1

template<typename Derived>
const PartialPivLU<PlainObject> Eigen::MatrixBase<Derived>::partialPivLu() const

Returns the partial-pivoting LU decomposition of *this.

This is defined in the LU module. #include <Eigen/LU>

template<typename Derived>
const MatrixPowerReturnValue<Derived> Eigen::MatrixBase<Derived>::pow(const RealScalar& p) const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise power to p use ArrayBase::pow .

Returns an expression of the matrix power to p of *this.

template<typename Derived>
const MatrixComplexPowerReturnValue<Derived> Eigen::MatrixBase<Derived>::pow(const std::complex<RealScalar>& p) const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise power to p use ArrayBase::pow .

Returns an expression of the matrix power to p of *this.

template<typename Derived> template<unsigned int UpLo>
MatrixBase<Derived>::template ConstSelfAdjointViewReturnType<UpLo>::Type Eigen::MatrixBase<Derived>::selfadjointView() const

This is the const version of MatrixBase::selfadjointView()

template<typename Derived> template<unsigned int UpLo>
MatrixBase<Derived>::template SelfAdjointViewReturnType<UpLo>::Type Eigen::MatrixBase<Derived>::selfadjointView()

Returns an expression of a symmetric/self-adjoint view extracted from the upper or lower triangular part of the current matrix

The parameter UpLo can be either Upper or Lower

Example:

Matrix3i m = Matrix3i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the symmetric matrix extracted from the upper part of m:" << endl
     << Matrix3i(m.selfadjointView<Upper>()) << endl;
cout << "Here is the symmetric matrix extracted from the lower part of m:" << endl
     << Matrix3i(m.selfadjointView<Lower>()) << endl;

Output:

Here is the matrix m:
 7  6 -3
-2  9  6
 6 -6 -5
Here is the symmetric matrix extracted from the upper part of m:
 7  6 -3
 6  9  6
-3  6 -5
Here is the symmetric matrix extracted from the lower part of m:
 7 -2  6
-2  9 -6
 6 -6 -5

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::setIdentity()

Writes the identity expression (not necessarily square) into *this.

Example:

Matrix4i m = Matrix4i::Zero();
m.block<3,3>(1,0).setIdentity();
cout << m << endl;

Output:

0 0 0 0
1 0 0 0
0 1 0 0
0 0 1 0

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::setIdentity(Index rows, Index cols)

Resizes to the given size, and writes the identity expression (not necessarily square) into *this.

Parameters
rows the new number of rows
cols the new number of columns

Example:

MatrixXf m;
m.setIdentity(3, 3);
cout << m << endl;

Output:

1 0 0
0 1 0
0 0 1

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::setUnit(Index i)

Set the coefficients of *this to the i-th unit (basis) vector.

Parameters
i index of the unique coefficient to be set to 1

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.

template<typename Derived>
Derived& Eigen::MatrixBase<Derived>::setUnit(Index newSize, Index i)

Resizes to the given newSize, and writes the i-th unit (basis) vector into *this.

Parameters
newSize the new size of the vector
i index of the unique coefficient to be set to 1

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.

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::sin() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise sine use ArrayBase::sin .

Returns an expression of the matrix sine of *this.

template<typename Derived>
const MatrixFunctionReturnValue<Derived> Eigen::MatrixBase<Derived>::sinh() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise hyperbolic sine use ArrayBase::sinh .

Returns an expression of the matrix hyperbolic sine of *this.

template<typename Derived>
const MatrixSquareRootReturnValue<Derived> Eigen::MatrixBase<Derived>::sqrt() const

This function requires the unsupported MatrixFunctions module. To compute the coefficient-wise square root use ArrayBase::sqrt .

Returns an expression of the matrix square root of *this.

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::squaredNorm() const

Returns , for vectors, the squared l2 norm of *this, and for matrices the Frobenius norm. In both cases, it consists in the sum of the square of all the matrix entries. For vectors, this is also equals to the dot product of *this with itself.

template<typename Derived>
RealScalar Eigen::MatrixBase<Derived>::stableNorm() const

Returns the l2 norm of *this avoiding underflow and overflow. This version use a blockwise two passes algorithm: 1 - find the absolute largest coefficient s 2 - compute $ s \Vert \frac{*this}{s} \Vert $ in a standard way

For architecture/scalar types supporting vectorization, this version is faster than blueNorm(). Otherwise the blueNorm() is much faster.

template<typename Derived>
void Eigen::MatrixBase<Derived>::stableNormalize()

Normalizes the vector while avoid underflow and overflow

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 method is analogue to the normalize() method, but it reduces the risk of underflow and overflow when computing the norm.

template<typename Derived>
const PlainObject Eigen::MatrixBase<Derived>::stableNormalized() const

Returns an expression of the quotient of *this by its own norm while avoiding underflow and overflow.

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 method is analogue to the normalized() method, but it reduces the risk of underflow and overflow when computing the norm.

template<typename Derived>
Scalar Eigen::MatrixBase<Derived>::trace() const

Returns the trace of *this, i.e. the sum of the coefficients on the main diagonal.

*this can be any matrix, not necessarily square.

template<typename Derived> template<unsigned int Mode>
MatrixBase<Derived>::template TriangularViewReturnType<Mode>::Type Eigen::MatrixBase<Derived>::triangularView()

Returns an expression of a triangular view extracted from the current matrix

The parameter Mode can have the following values: Upper, StrictlyUpper, UnitUpper, Lower, StrictlyLower, UnitLower.

Example:

Matrix3i m = Matrix3i::Random();
cout << "Here is the matrix m:" << endl << m << endl;
cout << "Here is the upper-triangular matrix extracted from m:" << endl
     << Matrix3i(m.triangularView<Eigen::Upper>()) << endl;
cout << "Here is the strictly-upper-triangular matrix extracted from m:" << endl
     << Matrix3i(m.triangularView<Eigen::StrictlyUpper>()) << endl;
cout << "Here is the unit-lower-triangular matrix extracted from m:" << endl
     << Matrix3i(m.triangularView<Eigen::UnitLower>()) << endl;
// FIXME need to implement output for triangularViews (Bug 885)

Output:

Here is the matrix m:
 7  6 -3
-2  9  6
 6 -6 -5
Here is the upper-triangular matrix extracted from m:
 7  6 -3
 0  9  6
 0  0 -5
Here is the strictly-upper-triangular matrix extracted from m:
 0  6 -3
 0  0  6
 0  0  0
Here is the unit-lower-triangular matrix extracted from m:
 1  0  0
-2  1  0
 6 -6  1

template<typename Derived> template<unsigned int Mode>
MatrixBase<Derived>::template ConstTriangularViewReturnType<Mode>::Type Eigen::MatrixBase<Derived>::triangularView() const

This is the const version of MatrixBase::triangularView()

template<typename Derived> template<typename T>
const CwiseBinaryOp<internal::scalar_product_op<T, Scalar>, Constant<T>, Derived> operator*(const T& scalar, const StorageBaseType& expr)

Template parameters
T is the scalar type of scalar. It must be compatible with the scalar type of the given expression.
Returns an expression of expr scaled by the scalar factor scalar