Finding elements that match a pattern. This gives the elements of the list which match the pattern x^_. Here is the total number of elements which match the pattern.

Finding the structure of polynomials written in expanded form. Here is a polynomial in two variables. This is the polynomial in expanded form.

In many practical situations it is convenient to consider limits in which a fixed amount of something is concentrated into an infinitesimal region. Ordinary mathematical ...

Mathematica allows you to use special notation for many common operators. For example, although internally Mathematica represents a sum of two terms as Plus[x,y], you can ...

DirichletCharacter[k, j, n] gives the Dirichlet character \[Chi] {k, j} (n) with modulus k and index j.

Fold[f, x, list] gives the last element of FoldList[f, x, list].

SinIntegral[z] gives the sine integral function Si(z).

This package contains descriptive statistics for multivariate data and distributions derived from the multivariate normal distribution. Distributions are represented in the ...

Disk[{x, y}, r] is a two-dimensional graphics primitive that represents a filled disk of radius r centered at the point x, y. Disk[{x, y}] gives a disk of radius 1. Disk[{x, ...

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.