Re: [petsc-dev] VecAXPY() in loops in TS

Even adjusting the array passed in will be worth it. Should MAXPY have an optional constant scale factor, does it come up enough? Barry On Feb 18, 2011, at 5:03 PM, Jed Brown wrote:

On Fri, Feb 18, 2011 at 19:48, Barry Smith <[email protected]> wrote: Can some of the VecAXPY() calls in loops in TS be replaced with single VecMAXPY() calls? For example

for (j=0; j<r; j++) { ierr = VecAXPY(gl->Z,-shift*u[i*r+j],X[j]);CHKERRQ(ierr); }

They can, but we would have to create a temporary array to hold the coefficients and run the loop to fill the coefficients into that array. I recall intending to do that when I first wrote this, but clearly it never happened.