# while

## Purpose

Repeat statements an indefinite number of times.

## Synopsis

    while expression
        statements
    end

## Description

`while` repeats `statements` an indefinite number of times. The `statements` are executed while the `expression` has all nonzero elements. The `expression` is usually of the form

    expression rop expression

where `rop` is ==, <, >, <=, >=, or ~=.

The scope of a `while` statement is always terminated with a matching `end`.

## Examples

The variable `eps` is a tolerance used to determine such things as near singularity and rank. Its initial value is the machine epsilon, the distance from 1.0 to the next largest floating-point number on your machine. Its calculation demonstrates `while` loops:

    eps = 1;
    while (1+eps) > 1
        eps = eps/2;
    end
    eps = eps*2

## See Also

    all, any, break, end, for, if, return

(c) Copyright 1994 by The MathWorks, Inc.