Cases

Cases[, , ... , pattern] gives a list of the that match the pattern.

Cases[, ... , pattern -> rhs] gives a list of the values of rhs corresponding to the that match the pattern.

Cases[expr, pattern, levspec] gives a list of all parts of expr on levels specified by levspec which match the pattern.

Cases[expr, pattern -> rhs, levspec] gives the values of rhs which match the pattern.

Example: Cases[2, x, 4, _Integer] .

The first argument to Cases need not have head List.

Cases[expr, pattern, levspec, n] gives the first n parts in expr which match the pattern.

Level specifications are described in Section A.3.6.

See The Mathematica Book: Section 2.3.2.

See also: Select, Position, ReplaceList, Collect.

Related package: Statistics`DataManipulation`.

Further Examples