InverseFourier[list] finds the discrete inverse Fourier transform of a list of complex numbers.
InverseZTransform[expr, z, n] gives the inverse Z transform of expr. InverseZTransform[expr, {z_1, z_2, ...}, {n_1, n_2, ...}] gives the multiple inverse Z transform of expr.
LyapunovSolve[a, c] finds a solution x of the matrix Lyapunov equation a.x + x.a\[ConjugateTranspose] == c.LyapunovSolve[a, b, c] solves a.x + x.b == c.LyapunovSolve[{a, d}, ...
NProduct[f, {i, i_min, i_max}] gives a numerical approximation to the product \[Product]i = i_min i_max f.NProduct[f, {i, i_min, i_max, di}] uses a step di in the product.
ReplacePart[expr, i -> new] yields an expression in which the i\[Null]\[Null]^th part of expr is replaced by new. ReplacePart[expr, {i_1 -> new_1, i_2 -> new_2, ...}] ...
SortBy
(Built-in Mathematica Symbol) SortBy[list, f] sorts the elements of list in the order defined by applying f to each of them.
Total
(Built-in Mathematica Symbol) Total[list] gives the total of the elements in list. Total[list, n] totals all elements down to level n. Total[list, {n}] totals elements at level n. Total[list, {n_1, n_2}] ...
A possible way of working with permutations is by relating them to the reorderings of the elements of a list. This is the standard point of view in the combinatorial approach ...
TetGenGetPointMarkers[expr] returns the point markers in a TetGen expression.
TetGenSetPointMarkers[expr, markers] sets the point markers in a TetGen expression.