Count[list, pattern] gives the number of elements in list that match pattern. Count[expr, pattern, levelspec] gives the total number of subexpressions matching pattern that ...

Diagonal[m] gives the list of elements on the leading diagonal of the matrix m.Diagonal[m, k] gives the elements on the k\[Null]^th diagonal of m.

Dimensions[expr] gives a list of the dimensions of expr. Dimensions[expr, n] gives a list of the dimensions of expr down to level n.

FindDivisions[{x_min, x_max}, n] finds a list of about n "nice" numbers that divide the interval around x_min to x_max into equally spaced parts. FindDivisions[{x_min, x_max, ...

Insert[list, elem, n] inserts elem at position n in list. If n is negative, the position is counted from the end. Insert[expr, elem, {i, j, ...}] inserts elem at position {i, ...

RotateLeft[expr, n] cycles the elements in expr n positions to the left. RotateLeft[expr] cycles one position to the left. RotateLeft[expr, {n_1, n_2, ...}] cycles elements ...

RotateRight[expr, n] cycles the elements in expr n positions to the right. RotateRight[expr] cycles one position to the right. RotateRight[expr, {n_1, n_2, ...}] cycles ...

Share[expr] changes the way expr is stored internally, to try and minimize the amount of memory used. Share[] tries to minimize the memory used to store all expressions.

Mathematically, sufficient conditions for a local minimum of a smooth function are quite straightforward: x^* is a local minimum if ∇f(x^*)=0 and the Hessian ∇^2f(x^*) is ...

"Calling .NET from Mathematica" describes using .NET/Link to allow you to call from Mathematica into .NET, thereby extending the Mathematica environment to include the ...