Much of what Mathematica does revolves around manipulating structured expressions. But you can also use Mathematica as a system for handling unstructured strings of text. ...

ReplaceList[expr, rules] attempts to transform the entire expression expr by applying a rule or list of rules in all possible ways, and returns a list of the results ...

FileNames[] lists all files in the current working directory. FileNames[form] lists all files in the current working directory whose names match the string pattern form. ...

Although Mathematica matches patterns in a purely structural fashion, its notion of structural equivalence is quite sophisticated. In particular, it takes account of ...

DiskMatrix[r] gives a matrix whose elements are 1 in a disk-shaped region of radius r, and are otherwise 0.DiskMatrix[r, w] gives a w*w matrix containing a disk of 1s with ...

Options[symbol] gives the list of default options assigned to a symbol. Options[expr] gives the options explicitly specified in a particular expression such as a graphics ...

Everything that Mathematica does can be thought of as derived from its ability to apply general transformation rules to arbitrary symbolic expressions. The Mathematica ...

MatrixPlot[m] generates a plot that gives a visual representation of the values of elements in a matrix.

A foundational idea in Mathematica is that all expressions—whatever they may represent—ultimately have a uniform tree-like structure.

Mathematica provides various ways to set up conditionals, which specify that particular expressions should be evaluated only if certain conditions hold. Conditional ...