public SDVariable lstsq(SDVariable matrix, SDVariable rhs, double l2_reguralizer, boolean fast) {
    SDValidation.validateNumerical("Lstsq", "matrix", matrix);
    SDValidation.validateNumerical("Lstsq", "rhs", rhs);
    return new org.nd4j.linalg.api.ops.custom.Lstsq(sd,matrix, rhs, l2_reguralizer, fast).outputVariable();
  }