Imlemented by Abinash Singh During FOSSEE Semester Long Fellowship 2024

1 files changed, 25 insertions, 0 deletions

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+/*
+Description
+    The inverse of the permute function.
+    The expression
+        ipermute (permute (A, perm), perm)
+    returns the original array A.
+Calling Sequence
+    ipermute (A, iperm)
+*/
+function B = ipermute(A, perm)
+    // ipermute : Inverse permute the dimensions of a matrix A.
+    // B = ipermute(A, perm) returns the array A with dimensions inverted
+    // according to the permutation vector `perm`.
+    // Validate the permutation vector
+    if max(size(perm)) ~= ndims(A) || or(gsort(perm, "g", "i") ~= 1:ndims(A))
+        error('Permutation vector must contain unique integers from 1 to ndims(A).');
+    end
+    // Compute the inverse permutation vector
+    invPerm = zeros(size(perm,1),size(perm , 2));
+    for i = 1:max(size(perm))
+        invPerm(perm(i)) = i;
+    end
+    // Use the permute function with the inverse permutation
+    B = permute(A, invPerm);
+endfunction