rationalize

static VALUE
nucomp_rationalize(int argc, VALUE *argv, VALUE self)
{
    get_dat1(self);

    rb_scan_args(argc, argv, "01", NULL);

    if (k_inexact_p(dat->imag) || f_nonzero_p(dat->imag)) {
       VALUE s = f_to_s(self);
       rb_raise(rb_eRangeError, "can't convert %s into Rational",
                StringValuePtr(s));
    }
    return rb_funcall2(dat->real, rb_intern("rationalize"), argc, argv);
}