Originally Posted by

**mecej4**
B*b + C*c is also a vector, and can be computed as such before solving the simultaneous equations. Let us call the result q. Then, the equation set to solve is A*x = q.

thanks

i got it

Many mathematical expressions that look reasonable, such as your result for x, fall into the category of "bad idea" in a numerical computation. One such is computing the inverse of a matrix as a stepping-stone to the solution of simultaneous equations. Sparse solvers will let you obtain the solution of A x = q without having to compute the inverse.

Then i want to ask for a more question

is that sparse matrix can only solve for square matrix??

if i want B*b (B=50*49 matrix , b=49*1 matrix )

imsl_f_mat_mul_rect_coordinate can realize it?

if it can , can you teach me how to do

thank you very much

Which solver should you use? That depends on whether A is banded or not. Besides that, for a if A is only 10 X 10 there is not enough inducement to exploit sparsity.