[GiNaC-list] parsing of declared functions with ginac 1.5

Tony Stoecker t.stoecker at fz-juelich.de
Wed Dec 9 17:52:58 CET 2009


Hi All:

I am happily using GiNaC since version 1.3. With version 1.5 I have the
problem that parsing of declared functions does not work anymore (the way  I
am using it).

The stupid example below works fine with version 1.4 but fails with version
1.5:

terminate called after throwing an instance of 'GiNaC::parse_error'
  what():  GiNaC: parse error at line 0, column 0: no function "floor" with 1
arguments
[GiNaC::ex GiNaC::parser::parse_identifier_expr()(parser/parser.cpp:66)]


Did I miss something in the declaration to introduce the new function to the
parser? Any help would be very much appreciated as I could not find the answer
in the tutorial / mailing list.

Cheers,
Tony



#include "ginac/ginac.h"

static GiNaC::ex floor_evalf(const GiNaC::ex &x){
        if (!GiNaC::is_a<GiNaC::numeric>(x) ) return x;
        GiNaC::ex xn = GiNaC::ex_to<GiNaC::numeric>(x);
        return ((int) GiNaC::ex_to<GiNaC::numeric>(xn).to_double()  );
}

DECLARE_FUNCTION_1P(floor)
REGISTER_FUNCTION(floor, evalf_func(floor_evalf))

using namespace std;
using namespace GiNaC;

int main() {

        symbol x("x");
        lst syms;  syms.append(x);
        lst nums; nums.append(1.9);

        //parsing from string does not work with version 1.5
        ex p("floor(x)",syms);
        cout << syms << "=" << nums << " ; " << p << "="
                << evalf(p.subs(syms,nums)) << endl;
  exit(0);

}



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