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#Example: "EpimorphismStandardPresentation-i" . . based on manual example
#(demonstrates interactive `EpimorphismStandardPresentation' usage)
#vars: F, x, y, z, w, a, b, R, Q, procId, G, phi, lev;
#options:
F := FreeGroup(6, "F");
## For printing GAP uses the symbols F1, ... for the generators of F
x := F.1; y := F.2; z := F.3; w := F.4; a := F.5; b := F.6;
R := [x^3 / w, y^3 / w * a^2 * b^2, w^3 / b,
Comm (y, x) / z, Comm (z, x), Comm (z, y) / a, z^3 ];
Q := F / R;
procId := PqStart( Q );
G := Pq( procId : Prime := 3, ClassBound := 3 );
lev := InfoLevel(InfoANUPQ); # Save current InfoANUPQ level
SetInfoLevel(InfoANUPQ, 2);; # To see computation time data
## It is not necessary to pass the `Prime' option to
## `EpimorphismStandardPresentation' since it was previously
## passed to `Pq':
phi := EpimorphismStandardPresentation( procId : ClassBound := 3 );
## Image of phi should be isomorphic to G ...
## let's check the order is correct:
Size( Image(phi) );
## `StandardPresentation' and `EpimorphismStandardPresentation'
## behave like attributes, so no computation is done when
## either is called again for the same process ...
StandardPresentation( procId : ClassBound := 3 );
## No timing data was Info-ed since no computation was done
SetInfoLevel(InfoANUPQ, lev);; # Restore previous InfoANUPQ level
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