PySparse Krylov method not modifying "initial guess"
<p>I am using the Krylov solve method in the PySparse package, and it is not "modifying" the initial guess I am feeding it, and merely returning the initial value despite that being very much not the solution.</p>

<p>Here is the block of code I'm using:</p>

<pre><code>    self.matrix2vector(_chargeDensity, self.rhoVec)
    self.matrix2vector(self.phi, self.phiVec)

    info, iter, relres = krylov.pcg(self.L.to_sss(), self.rhoVec, self.phiVec, 1e-12, 2000)

    print "info: ", info
    print "iter: ", iter
    print "relres: ", relres

    self.vector2matrix(self.phiVec, self.phi)
    print self.rhoVec
    print self.phi
</code></pre>

<p>both phi and rhoVec are unmodified in the process, info is returning 0, iter is returning 9 or so, and relres is ~10^-17. What is going on here?</p>
