Let $G$ be a finite group and let $M(G)=H^2(G,\mathbb{C}^*)$ be its Schur multiplier. For "small" groups I can compute the Schur multiplier by hand in terms of corresponding roots of unity.
However, for "large" groups I have truble even to determine if the Schur multiplier of a group is trivial, or if the Schur multiplier of two groups of the same cardinality are isomorphic.
I thought about using GAP, however I think that my groups are too large for it also.
The groups are of order about $10^{50}$, however they are semidirect product of two Sylow subgroups.
I will be happy to hear any idea.