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Q138042: PRB: MOD() with One Negative Number Returns Incorrect Result

Article: Q138042
Product(s): Microsoft FoxPro
Version(s): WINDOWS:2.6a,3.0
Operating System(s): 
Keyword(s): 
Last Modified: 03-AUG-2000

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The information in this article applies to:

- Microsoft FoxPro for Windows, version 2.6a 
- Microsoft Visual FoxPro for Windows, version 3.0 
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SYMPTOMS
========

When using the MOD() function with one negative number and the expected result
is the numerator, FoxPro returns the wrong value. For example, MOD(9,-10)
returns -1. The correct result should be 9.

CAUSE
=====

This occurs because the MOD() function was designed to maintain compatibility
with the dBASE MOD() function, which also returns this result.

NOTE: dBASE is manufactured by Borland International Inc., a vendor independent
of Microsoft; we make no warranty, implied or otherwise, regarding this
product's performance or reliability.

RESOLUTION
==========

Create a function similar to the following and use this function instead of
MOD().

     FUNCTION INTMOD
     PARAMETER x,y         && where x is the numerator, y is the denominator
     z = x - INT(x/y)*y
     RETURN z              && where z is the expected result

STATUS
======

This behavior is by design.


Additional query words: VFoxWin FoxWin akz

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbFoxproSearch kbFoxPro260a kbVFP300
Version           : WINDOWS:2.6a,3.0

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