bugfix for a = a * b; when a has to be resized

(transplanted from a551107ccea8fe027d2672cb82f6b70e741bb996
)
This commit is contained in:
Gael Guennebaud 2009-07-20 10:35:47 +02:00
parent 8302ce6cdc
commit fa44566305
2 changed files with 25 additions and 2 deletions

View File

@ -493,6 +493,9 @@ class Matrix
else resize(other.rows(), other.cols());
}
template<typename MatrixType, typename OtherDerived, bool EvalBeforeAssigning = (int(OtherDerived::Flags) & EvalBeforeAssigningBit) != 0>
struct ei_matrix_set_selector;
/** \internal Copies the value of the expression \a other into \c *this with automatic resizing.
*
* *this might be resized to match the dimensions of \a other. If *this was a null matrix (not already initialized),
@ -507,8 +510,8 @@ class Matrix
template<typename OtherDerived>
EIGEN_STRONG_INLINE Matrix& _set(const MatrixBase<OtherDerived>& other)
{
_resize_to_match(other);
return Base::operator=(other);
ei_matrix_set_selector<Matrix,OtherDerived>::run(*this,other.derived());
return *this;
}
/** \internal Like _set() but additionally makes the assumption that no aliasing effect can happen (which
@ -536,6 +539,20 @@ class Matrix
}
};
template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
template<typename MatrixType, typename OtherDerived>
struct Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>::ei_matrix_set_selector<MatrixType,OtherDerived,true>
{
static void run(MatrixType& dst, const OtherDerived& src) { dst._set_noalias(src.eval()); }
};
template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
template<typename MatrixType, typename OtherDerived>
struct Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>::ei_matrix_set_selector<MatrixType,OtherDerived,false>
{
static void run(MatrixType& dst, const OtherDerived& src) { dst._set_noalias(src); }
};
/** \defgroup matrixtypedefs Global matrix typedefs
*
* \ingroup Core_Module

View File

@ -42,4 +42,10 @@ void test_product_large()
m = (v+v).asDiagonal() * m;
VERIFY_IS_APPROX(m, MatrixXf::Constant(N,3,2));
}
{
// test deferred resizing in Matrix::operator=
MatrixXf a = MatrixXf::Random(10,4), b = MatrixXf::Random(4,10), c = a;
VERIFY_IS_APPROX((a = a * b), (c * b).eval());
}
}