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Tr

FilledSmallSquare Tr[list] finds the trace of the matrix or tensor list.

FilledSmallSquare Tr[list, f] finds a generalized trace, combining terms with f instead of Plus.

FilledSmallSquare Tr[list, f, n] goes down to level n in list.

FilledSmallSquare Tr[list] sums the diagonal elements list[[i, i, ... ]].

FilledSmallSquare Tr works for rectangular as well as square matrices and tensors.

FilledSmallSquare Tr can be used on SparseArray objects.

FilledSmallSquare See Section 3.7.7.

FilledSmallSquare See also: Total, Transpose, Det, DiagonalMatrix, Eigenvalues.

FilledSmallSquare New in Version 4.

Further Examples