Fix pinv bug with 0 values introduced in cset 16b0cd465ecd. * pinv.cc (Fpinv): Add %!tests for diagonal matrices * CDiagMatrix.cc (pseudo_inverse), dDiagMatrix.cc (pseudo_inverse), fCDiagMatrix.cc (pseudo_inverse), fDiagMatrix.cc (pseudo_inverse): Don't skip assigning 0 to retval element when matrix element is 0 since retval memory is not initialized to 0.

#include "mex.h"

void
mexFunction (int nlhs, mxArray *plhs[],
             int nrhs, const mxArray *prhs[])
{
  const char *nm;

  nm = mexFunctionName ();
  mexPrintf ("You called function: %s\n", nm);
  if (strcmp (nm, "myfunc") == 0)
    mexPrintf ("This is the principal function\n", nm);

  return;
}