[GiNaC-devel] Substitution of wildcards

[Vladimir V. Kisil]

>>>>> On Fri, 09 Jun 2017 16:58:37 +0100, "Vladimir V. Kisil" <kisilv at maths.leeds.ac.uk> said:

>>>>> On Wed, 7 Jun 2017 18:26:47 +0200, Jan Rheinländer <jrheinlaender at gmx.de> said:
    JR> Hi, I'm wondering what is going on here (ginsh output):

    >>> subs($1 * x + 1/2 * x^2 * $2, match(a * x + b, $1 + x * $2));
    JR> b*a+1/2*a^3

    JR> What happened to "x" ? The match by itself correctly finds

    The effect, which you are expecting, is achieved by by
  subs_options::no_pattern

#include <ginac/ginac.h>
using namespace std;
using namespace GiNaC;

int main(){
	realsymbol x("x"), a("a"), b("b");
	wildcard w0(0),  w1(1);
	exmap repl;
	(a * x + b).match(w0 + x * w1,repl);
	cout << (w0 * x + pow(x,2) * w1 / 2).subs(repl,subs_options::no_pattern) << endl;
	// -> b*x+1/2*a*x^2
}

-- 
Vladimir V. Kisil                 http://www.maths.leeds.ac.uk/~kisilv/
  Book:     Geometry of Mobius Transformations     http://goo.gl/EaG2Vu
  Software: Geometry of cycles          http://moebinv.sourceforge.net/