# More digits from octave

Hi, how can I get all the 15/16 digits from a command like pi = octave('pi')?

More digits from octave

Hi, how can I get all the 15/16 digits from a command like pi = octave('pi')?

add a comment

1

Hi, I found myself a solution, for instance:

```
a=Matrix(RR,octave('sprintf("%.16e ",rand(1,4))'))
```

0

Starting Octave just to get a numerical value of pi is unnecessarily slow.

If you need a floating-point approximation to pi, I would suggest:

```
sage: pi = RDF.pi()
sage: pi
3.141592653589793
```

But maybe you have other reasons to use Octave?

Sorry, try this instead a=octave('0.123456789'). I chose pi just to be short. I get a=0.123457, lost two digits.

0

As far as I know, the "octave" command really just gets you an interface that allows you to pass strings as "typed in to octave" and get you back strings as printed by octave. So:

```
octave:1> 0.123456789
ans = 0.12346
```

suggests octave is naturally stingy with printing digits. In order to get more digits back via the octave interface, you should do whatever you do to normally coerce octave to print more digits. Perhaps https://www.gnu.org/software/octave/d... helps.

Please start posting anonymously - your entry will be published after you log in or create a new account.

Asked: ** 2016-07-22 12:37:53 +0100 **

Seen: **845 times**

Last updated: **Jul 29 '16**

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.