Subject: [ublas] axpy documentation bug or axpy bug?
From: Nizar Khalifa Sallem (nksallem_at_[hidden])
Date: 2010-11-09 07:18:14
I am running in big trouble with axpy_prod.
The doc says: template<class V, class E1, class E2> BOOST_UBLAS_INLINE
V & axpy_prod (const matrix_expression< E1 > &e1, const
vector_expression< E2 > &e2, V &v, bool init=true)
computes v += A x or v = A x in an optimized fashion
but when compiling gcc 4.4.3 said that the boolean parameter can not
be constant which was a surprise for me. After checking the
boost/numeric/ublas/operation.hpp header it seems that the boolean
parameter is now used to say if the matrix is a column major one still
it is filled by the axpy_prod function which I don't completely
understand. Either the axpy_prod can guess the storage type of the
matrix in which case there is no point in passing such param or it
doesn't and in this cas the boolean parameter should be constant.
Also how can man tell axpy_pord to compute v = Ax and not v+=Ax or v =
A'x and not v+=A'x since it is not clear in the doc.
PS: I am running boost-1.40 on a ubuntu