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 appear at the levels in expr specified by levelspec.
Level specifications are described in Section A.3.6.
See Section 1.8.5 and Section 2.3.2.
See also: FreeQ, MemberQ, Cases, Select, Position.
Related package: Statistics`DataManipulation`.
New in Version 1.