static void apply( const tensor_type & tensor ,
const MatrixValue * const a ,
const VectorValue * const x ,
VectorValue * const y )
{
const size_type nDim = tensor.dimension();
// Loop over i
for ( size_type i = 0; i < nDim; ++i) {
VectorValue ytmp = 0;
// Loop over k for this i
const size_type nk = tensor.num_k(i);
const size_type kBeg = tensor.k_begin(i);
const size_type kEnd = kBeg + nk;
for (size_type kEntry = kBeg; kEntry < kEnd; ++kEntry) {
const size_type k = tensor.k_coord(kEntry);
const MatrixValue ak = a[k];
const VectorValue xk = x[k];
// Loop over j for this i,k
const size_type nj = tensor.num_j(kEntry);
const size_type jBeg = tensor.j_begin(kEntry);
const size_type jEnd = jBeg + nj;
for (size_type jEntry = jBeg; jEntry < jEnd; ++jEntry) {
const size_type j = tensor.j_coord(jEntry);
ytmp += tensor.value(jEntry) * ( a[j] * xk + ak * x[j] );
}
}
y[i] += ytmp ;
}
}
