Sometimes you may want to set up functions where certain arguments, if omitted, are given "default values". The pattern x_:v stands for an object that can be omitted, and if ...

Since lists are just a particular kind of expression, it will come as no surprise that you can refer to parts of any expression much as you refer to parts of a list. This ...

"Sound" describes how you can take functions and lists of data and produce sounds from them. Here we discuss how sounds are represented in Mathematica. Mathematica treats ...

FactorialMomentGeneratingFunction[dist, t] gives the factorial moment generating function for the symbolic distribution dist as a function of the variable t. ...

GraphicsComplex[{pt_1, pt_2, ...}, data] represents a graphics complex in which coordinates given as integers i in graphics primitives in data are taken to be pt_i.

SortBy[list, f] sorts the elements of list in the order defined by applying f to each of them.

Total[list] gives the total of the elements in list. Total[list, n] totals all elements down to level n. Total[list, {n}] totals elements at level n. Total[list, {n_1, n_2}] ...

Assuming[assum, expr] evaluates expr with assum appended to $Assumptions, so that assum is included in the default assumptions used by functions such as Refine, Simplify, and ...

x + y + z represents a sum of terms.

f /: lhs := rhs assigns rhs to be the delayed value of lhs, and associates the assignment with the symbol f.