Reverse concatenation: separate a data array along a specified dimension.

[A B]=INVERSE_CAT(DIM,C) splits array C along dimension, DIM, returning sub-arrays A and B.

Examples:
M = [1 2 3; 4 5 6; 7 8 9];
C = cat(2,M,M)
[A B] = inverse_cat(2,C) ... returns A=M and B=M
[A B] = inverse_cat(1,rot90(C)) ... returns A=rot90(M) B=rot90(M)
[A B] = inverse_cat(3,cat(3,M,M)) ... returns A=M and B=M

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Note: There are certainly more efficient ways to separate concatenated data. Suggestions for improvement are much appreciated.

*Thanks to Jan Simon for insightful comments.