MATLAB - Solving multiple linear systems where A (the matrix to be inverted) is the same -


i have following code excerpt:

%suppose 40000 40000 matrix phi = zeros(40000,1);   t = 1:360       phivec = -phi;       phi = full(a\sparse(phivec)); end

for each t, solve system a*x = phivec. t=1, phivec given. t>1, phivec comes phivec @ t-1. there way speed process, since same each t. did try invert before loop starts , matrix multiplication, since huge (40000*40000), it's taking lot of memory. there way invert once save time?


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