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 GNU Octave Manual Version 3 by John W. Eaton, David Bateman, Søren HaubergPaperback (6"x9"), 568 pagesISBN 095461206XRRP £24.95 (\$39.95)

### 1.3.2 Evaluation Notation

In the examples in this manual, results from expressions that you evaluate are indicated with ‘=>’. For example,

```sqrt (2)
=> 1.4142
```

You can read this as “`sqrt (2)` evaluates to 1.4142”.

In some cases, matrix values that are returned by expressions are displayed like this

```[1, 2; 3, 4] == [1, 3; 2, 4]
=> [ 1, 0; 0, 1 ]
```

and in other cases, they are displayed like this

```eye (3)
=>  1  0  0
0  1  0
0  0  1
```

in order to clearly show the structure of the result.

Sometimes to help describe one expression, another expression is shown that produces identical results. The exact equivalence of expressions is indicated with ‘==’. For example,

```rot90 ([1, 2; 3, 4], -1)
==
rot90 ([1, 2; 3, 4], 3)
==
rot90 ([1, 2; 3, 4], 7)
```
 ISBN 095461206X GNU Octave Manual Version 3 See the print edition