const ex &d, unsigned nth=1)
{
ex ed = e.diff(x, nth);
- if ((ed - d).compare(ex(0)) != 0) {
+ if (!(ed - d).is_zero()) {
switch (nth) {
case 0:
clog << "zeroth ";
ed = series_to_poly(ed);
d = series_to_poly(d);
- if ((ed - d).compare(ex(0)) != 0) {
+ if (!(ed - d).is_zero()) {
clog << "derivative of " << e << " by " << x << " returned "
<< ed << " instead of " << d << ")" << endl;
return 1;