Is there a way to solve wrong results when using (mod) operation?

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Abdulatif Alabdulatif 2014-4-20

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评论： Abdulatif Alabdulatif 2014-4-28

Hi all,

I am working with many (mod) operations to create my own functions in matlab. However, I face a problem of wrong results that are appears. For example,

***** Manuale calculations ***********

temp = (16667 * 16667 * 16667 ) = 4629907412963

temp = = 2533 * 4629907412963 = 11727555477035279

temp = temp % 25000

temp = 10279

***** Matlab calculations ***********

temp = (16667 * 16667 * 16667 )

temp = 2533 * 4.6299e+12

temp = 1.1728e+16

temp = mod (1.1728e+16 , 25000)

temp = 10280

******************************

As you can see, there are two different results even it is just one value! Also I have another

example with a huge difference between the two results.

Is there a convenient way to solve this issue?

Thanks in advance!

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Abdulatif Alabdulatif 2014-4-28

It works with the symbolic toolbox.

Thank you so much : )

Abdulatif Alabdulatif 2014-4-28

Both answers helps me

Thank you Geoff Hayes & Walter Roberson

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采纳的回答

Walter Roberson 2014-4-20

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You could work with int64 or uint64 datatype. That would postpone the problem.

To solve the problem (for most practical purposes) you would need to switch to a high precision arithmetic system, such as using the symbolic toolbox or using John D'Errico's File Exchange contribution "VPI"