MATLAB Answers

DSP Masters

How to seperate fractional and decimal part in a real number

Asked by DSP Masters
on 16 Nov 2011
Latest activity Answered by Walter Roberson
about 15 hours ago
Accepted Answer by Naz

Hi, Please help me in seperating fractional and decimal part in a real number. For example: If the value is '1.23', I need to seperate decimal part '1' and 'fractional part '0.23'.

Thanks and regards, soumya..


Jan Simon
on 16 Nov 2011

Are you talking of numbers or strings? The quotes in '1.23' might be misleading.

Jan Its my pet peeve when a poster poses a question and it is responded to with another unnecessary question. Yes, in Matlab syntax, '0.23' indicates a string, but it is really obvious that he meant 0.23. I guess my wish to responders is simply, 'Just answer the question already' !!

Jan Simon
on 13 Feb 2016 at 12:28

Some years later: @Jerry: Many questions in this forum are based on the inaccurate knowledge about the classes of variables. I tend to ask for a clarification instead of speculating of what seems obvious.


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5 Answers

Answer by Naz
on 16 Nov 2011
 Accepted answer

  1 Comment

That fails on negative numbers. For negative numbers, you need fract=number-ceil(number)

Answer by Resam Makvandi
on 26 Dec 2012

i think the better way is to use: number = 1.23; integ = fix(number); fract = abs(number - integ);

it works for both negative and positive values.


Answer by Are Mjaavatten
on 9 Feb 2016 at 15:39
Edited by Are Mjaavatten
on 9 Feb 2016 at 15:39


Walter Roberson
on 10 Feb 2016 at 14:35

The accepted answer by Naz does not use any intermediate variables. The task is to return each of the parts. Naz's solution happens to calculate one part and use it to calculate the other as well, but that does not make either one an intermediate variable.

Are Mjaavatten
on 13 Feb 2016 at 11:50

Point taken. I should be old enough to have learned to read the problem definition. Still, I think it is nice to have a single command for the fractional part.

Jan Simon
on 13 Feb 2016 at 12:17

What about rem instead of mod?

abs(rem(-0.123, 1))   % =>  0.123

Answer by Kh.Ehsanur Rahman about 20 hours ago

what if the number is -1.23.


Answer by Walter Roberson
about 15 hours ago
number = -1.23
integ = fix(number)
frac = mod(abs(number),1)


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