Hi! On 03/23/2011 03:39 PM, Michael Boyer wrote:
------------------------------------------------ #include<ginac/ginac.h> using namespace GiNaC;
int main() { possymbol x("x"); ex a = x;
if (a.info(info_flags::positive)) std::cout<< a<< " is positive\n"; else std::cout<< a<< " is _not_ positive\n";
a *= -1;
if (a.info(info_flags::negative)) std::cout<< a<< " is negative\n"; else std::cout<< a<< " is _not_ negative\n"; } ------------------------------------------------
The output I see is: x is positive -x is _not_ negative
Any idea why it cannot determine that -x is in fact negative?
It can and does determine that since 1.5.7. You must be using an older release. -richy. -- Richard B. Kreckel <http://www.ginac.de/~kreckel/>