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Topic: how to round to 2 decimal?
Replies: 12   Last Post: Oct 18, 2015 7:19 AM

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 Walter Roberson Posts: 5,173 Registered: 2/26/06
Re: how to round to 2 decimal?
Posted: Mar 4, 2008 10:29 AM

In article <fqjpgm\$3hp\$1@fred.mathworks.com>, Deo <spliers@hotmail.com> wrote:
>hey, how can I set my matlab program to round all the
>double numbers to 2 decimals

You cannot. There is no exact representation in floating point
for .01, .02, up to .99, except for 0.25, 0.50, and 0.75 which
have exact representations. If you were to try to round
(say) pi to 2 decimal places then the value stored internally
would not correspond to 3.14 but instead to approximately
3.14 + 2e-15

If you are only attempting to change what is displayed when
you specifically ask to output something, then you can
format the numbers using num2str or sprintf() using a format
such as '%0.2f' .
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Date Subject Author
3/4/08 Deo
3/4/08 Walter Roberson
3/4/08 PAR
10/18/15 Chaman Lal Dewangan
3/4/08 PAR
3/4/08 J
3/4/08 Walter Roberson
3/6/13 Nasser Abbasi
11/14/13 Marco
11/14/13 Derek Goring
6/9/15 yan mercal
6/9/15 Steven Lord