Commit 6b2b213d authored by Davis King's avatar Davis King

Added an overload of sparse_matrix_vector_multiply() that multiplies a dense

matrix with a sparse vector.
parent aee36c3d
......@@ -1003,10 +1003,60 @@ namespace dlib
// ----------------------------------------------------------------------------------------
}
template <
typename EXP,
typename sparse_vector_type,
typename T,
long NR,
long NC,
typename MM,
typename L
>
void sparse_matrix_vector_multiply (
const matrix_exp<EXP>& m,
const sparse_vector_type& v,
matrix<T,NR,NC,MM,L>& result
)
{
// make sure requires clause is not broken
DLIB_ASSERT(max_index_plus_one(v) <= (unsigned long)m.nc(),
"\t void sparse_matrix_vector_multiply()"
<< "\n\t Invalid inputs were given to this function"
<< "\n\t max_index_plus_one(v): " << max_index_plus_one(v)
<< "\n\t m.size(): " << m.size()
);
#endif // DLIB_SVm_SPARSE_VECTOR
result.set_size(m.nr(),1);
result = 0;
for (typename sparse_vector_type::const_iterator i = v.begin(); i != v.end(); ++i)
{
for (long r = 0; r < result.nr(); ++r)
{
result(r) += m(r, i->first)*i->second;
}
}
}
// ----------------------------------------------------------------------------------------
template <
typename EXP,
typename sparse_vector_type
>
matrix<typename EXP::type,0,1> sparse_matrix_vector_multiply (
const matrix_exp<EXP>& m,
const sparse_vector_type& v
)
{
matrix<typename EXP::type,0,1> result;
sparse_matrix_vector_multiply(m,v,result);
return result;
}
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_SVm_SPARSE_VECTOR
......@@ -618,6 +618,49 @@ namespace dlib
// ----------------------------------------------------------------------------------------
template <
typename EXP,
typename sparse_vector_type,
typename T,
long NR,
long NC,
typename MM,
typename L
>
void sparse_matrix_vector_multiply (
const matrix_exp<EXP>& m,
const sparse_vector_type& v,
matrix<T,NR,NC,MM,L>& result
);
/*!
requires
- max_index_plus_one(v) < m.nc()
- v == an unsorted sparse vector
ensures
- #result == m*v
(i.e. multiply m by the vector v and store the output in result)
!*/
// ----------------------------------------------------------------------------------------
template <
typename EXP,
typename sparse_vector_type
>
matrix<typename EXP::type,0,1> sparse_matrix_vector_multiply (
const matrix_exp<EXP>& m,
const sparse_vector_type& v
);
/*!
requires
- max_index_plus_one(v) < m.nc()
- v == an unsorted sparse vector
ensures
- returns m*v
(i.e. multiply m by the vector v and return the resulting vector)
!*/
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_SVm_SPARSE_VECTOR_ABSTRACT_
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment