public static double rowSparcity(Matrix mat) {
double nrows = mat.getNumRows();
double nsparse = 0;
for (int r = 0; r < nrows; r++) {
if (mat.getRow(r).sum() == 0) {
nsparse++;
}
}
return nsparse / nrows;
}
public static Vector diag(Matrix mat) {
Vector ret;
if (mat.getNumColumns() > mat.getNumRows()) {
ret = mat.getRow(0);
} else {
ret = mat.getColumn(0);
}
int rowcol = ret.getDimensionality();
for (int rc = 0; rc < rowcol; rc++) {
ret.setElement(rc, mat.getElement(rc, rc));
}
return ret;
}