# speye

## Purpose

Sparse identity matrix.

## Synopsis

    S = speye(m,n)
    S = speye(n)

## Description

`S = speye(m,n)` forms an `m`-by-`n` sparse matrix with 1s on the main diagonal.

`S = speye(n)` abbreviates `speye(n,n)`.

## Examples

`I = speye(1000)` forms the sparse representation of the 1000-by-1000 identity matrix, which requires only about 16 kilobytes of storage. This is the same final result as `I = sparse(eye(1000,1000))`, but the latter requires eight megabytes for temporary storage for the full representation.

## See Also

    spalloc, spones

(c) Copyright 1994 by The MathWorks, Inc.