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D.15.23.26 compareModules

Procedure from library modules.lib (see modules_lib).

Usage:
compareModules(M,N); or M==N; compares two Modules up to isomorphism

Return:
1 or 0, if the are ismomophic or aren't

Example:
 
LIB "modules.lib";
ring r;
matrix ma[2][2]=x,y,x,y;
Matrix m=ma;
Module M=image(m);
matrix na[2][1]=-y,x;
Matrix n=na;
M;
==> image | x y |
==>       | x y |
==> 
==> 
Module N=image(n);
N;
==> image | -y |
==>       | x  |
==> 
==> 
N==M;
==> 0
N=coker(n);
N;
==> cokernel | -y |
==>          | x  |
==> 
==> 
N==M;
==> 0