problems using plus_inf

Librairie C++ de calcul formel/ C++ symbolic computation library

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lukamar
Messages : 294
Inscription : ven. juin 30, 2017 9:55 am
Localisation : Zagreb, Croatia

problems using plus_inf

Message par lukamar » mer. nov. 01, 2017 8:59 am

Hi,
I have certain problems when trying to use some predefined gen such as plus_inf, zero, plus_one etc. Here's a minimal example (test.cc):

Code : Tout sélectionner

#include <giac/config.h>
#include <giac/gen.h>
#include <giac/unary.h>
#include <giac/giac.h>
#include <iostream>
using namespace giac;
using namespace std;

int main() {
gen g(plus_inf);
cout << g << endl;
return 0;
}
This program segfaults after being compiled with

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g++ -Wall -g test.cc -lgiac -lgmp
But when i replace "gen g(plus_inf)" with

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gen g(unsigned_inf)
the program works fine. As I see, unsigned_inf is defined using the identificateur constructor, while plus_inf is defined as symbolic(at_plus,unsigned_inf). I would like to understand what leads to crash. However, It's not a big deal if it remains unclear, as I can easily redefine infinities by copying the above mentioned definition from your code:

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gen g=symbolic(at_plus,unsigned_inf);
It works as expected.

parisse
Messages : 5084
Inscription : mar. déc. 20, 2005 4:02 pm
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Re: problems using plus_inf

Message par parisse » mer. nov. 01, 2017 3:21 pm

I don't know what happens, it might be related to the order objects are loaded.

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