
Ublas : 
From: Andreas Zilian (a.koelke_at_[hidden])
Date: 20071122 03:58:17
Hello ublas,
I would like to add a vector my_vec to a matrix my_mat as follows:
before:
0000 and XXX
0000
0000
0000
after:
0000
0XXX
0000
0000
I tried the construction:
ublas::subrange( ublas::row (my_mat, 1), 1, 4 ) += my_vec;
but the compiler (icpc) failed and stated the error:
error #137: expression must be a modifiable lvalue
t1 = t2;
^
A possible way to circumvent works:
ublas::matrix_row<matrix<double>> tmp (my_mat, 0);
ublas::subrange( tmp, 0, 8 ) += my_vec;
but I was wondering about performance issues on that solution.
So, my question is how is the reference solution to add a vector to
a subregion of a matrix?
Thanks in advance for your help,
Andreas.