Dear GAP Forum,
Vahid Dabbaghian asked:
How can I get the character value of an element of group G,
without checking that this element is in which conjugacy class
This depends a bit ob the representation G is given in, as well as the
representation that affords the character:
If G is a matrix group, and the character is given by the natural matrix
representation of G, you can use TraceMat.
If the character is given by the natural permutation representation, you can
check the number of fixed points:
Otherwise you'll somehow have to connect the group and the representation.
If you can define the representation as a homomorphism, you can use the trace of
the image of an element (though you should be aware that for very large groups
the calculation of homomorphism images might be tedious).
Otherwise I don't see a way how you could (even in theory) get the character
value without (at least implicitly) identifying the class of the element.
If this does not answer your question please give us a bit more detail about
what group and what character you are looking at.
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