public static int[] PseudoInverseWorkspace(Cdn.Dimension d)
{
int[] m = new int[] { d.Rows };
int[] n = new int[] { d.Columns };
var maxdim = System.Math.Max(d.Rows, d.Columns);
var mindim = System.Math.Max(d.Rows, d.Columns);
int[] nrhs = new int[] { maxdim };
double[] A = new double[d.Size()];
double[] b = new double[maxdim * maxdim];
double[] s = new double[mindim];
double[] rcond = new double[] { -1 };
double[] rank = new double[1];
double[] work = new double[1];
int[] lwork = new int[] { -1 };
int[] iwork = new int[1];
int[] info = new int[1];
int nlvl = (int)System.Math.Log(mindim / (25.0 + 1.0), 2) + 1;
int riwork = 3 * mindim * nlvl + 11 * mindim;
try
{
dgelsd_(m, n, nrhs, A, m, b, nrhs, s, rcond, rank, work, lwork, iwork, info);
return(new int[] { (int)work[0], riwork });
}
catch
{
return(new int[] { 12 * mindim + 2 * mindim * 25 + 8 * mindim * nlvl + mindim * maxdim + (int)System.Math.Pow(25.0 + 1.0, 2), riwork });
}
}
public static int QrWorkspace(Cdn.Dimension d)
{
int[] m = new int[] { d.Rows };
int[] n = new int[] { d.Columns };
double[] A = new double[d.Size()];
double[] tau = new double[d.Rows < d.Columns ? d.Rows : d.Columns];
double[] work = new double[1];
int[] lwork = new int[] { -1 };
int[] info = new int[1];
try
{
dgeqrf_(m, n, A, m, tau, work, lwork, info);
return((int)work[0]);
}
catch
{
return(d.Columns * 64);
}
}