docs: public static void setMatrix(final double[][] m1, final int[] r, final int c0, final int c1, final double[][] m2) {
      assert c0 <= c1 : ERR_INVALID_RANGE;
      assert c1 <= m1[0].length : ERR_MATRIX_DIMENSIONS;
      for(int i = 0; i < r.length; i++) {
        System.arraycopy(m2[i], 0, m1[r[i]], c0, c1 - c0);
      }
    }