orth orthogonal basis

## Syntax

    Q=orth(A)

## Arguments

A

  real or complex matrix

Q

  real or complex matrix

## Description

`Q=orth(A)` returns `Q`, an orthogonal basis for the span of `A`. Range(`Q`) = Range(`A`) and `Q'*Q=eye`.

The number of columns of `Q` is the rank of `A` as determined by the QR algorithm.

## Examples

    A=rand(5,3)*rand(3,4);
    [X,dim]=rowcomp(A);X=X';
    svd([orth(A),X(:,1:dim)])

## See also

- qr
- rowcomp
- colcomp
- range