Patterns stand for classes of expressions. They contain pattern objects that represent sets of possible expressions. Pattern objects. When several pattern objects with the ...

In some cases you may need to specify pattern sequences that are more intricate than things like x__ or x..; for such situations you can use PatternSequence[p_1,p_2,…]. ...

Using the objects described in "Introduction to Patterns", you can set up patterns for many kinds of expressions. In all cases, you must remember that the patterns must ...

Specifying patterns that involve alternatives. This defines h to give p when its argument is either a or b. The first two cases give p.

Introduction Finding Expressions That Match a Pattern Naming Pieces of Patterns

Groups admit many different representations. In particular, all finite groups can be represented as permutation groups, that is, they are always isomorphic to a subgroup of ...

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 ...

Permutations are basic elements in algebra. They have a natural non-commutative product (as matrices do as well), and hence can encode highly nontrivial structures in a ...

Functions to pick out pieces of polynomials. Here is an algebraic expression. This gives the coefficient of x in e.

Turning conditions into numbers. Boole[expr] is a basic function that turns True and False into 1 and 0. It is sometimes known as the characteristic function or indicator ...