public Matrix2d preMultBy(Matrix2d leftSide) {
Matrix2d ret = new Matrix2d(touchvgPINVOKE.Matrix2d_preMultBy(swigCPtr, Matrix2d.getCPtr(leftSide)), false);
if (touchvgPINVOKE.SWIGPendingException.Pending) throw touchvgPINVOKE.SWIGPendingException.Retrieve();
return ret;
}