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Task/Matrix-arithmetic/00DESCRIPTION

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+For a given matrix, return the [[wp:Determinant|determinant]] and the [[wp:Permanent|permanent]] of the matrix.
+
+The determinant is given by
+:<math>\det(A) = \sum_\sigma\sgn(\sigma)\prod_{i=1}^n M_{i,\sigma_i}</math>
+while the permanent is given by
+: <math> \operatorname{perm}(A)=\sum_\sigma\prod_{i=1}^n M_{i,\sigma_i}</math>
+In both cases the sum is over the permutations <math>\sigma</math> of the permutations of 1, 2, ..., ''n''. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see [[wp:Parity of a permutation|parity of a permutation]].)
+
+More efficient algorithms for the determinant are known: [[LU decomposition]], see for example [[wp:LU decomposition#Computing the determinant]]. Efficient methods for calculating the permanent are not known.
+
+;Cf.:
+* [[Permutations by swapping]]