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Q164359: BUG: Incorrect Evaluation of Equation with Variables

Article: Q164359
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbvfp kbvfp500bug kbvfp600bug
Last Modified: 05-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

In Visual FoxPro 5.0 and higher, an equation that contains variables may not be
evaluated correctly.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

In the Command window, issue the following commands:

     SET DECIMALS TO 5
     mVar = 1
     ? mVar + (1048575+(mVar/1000)) = 1048576.001

The value .T. (True) should be echoed to the screen but .F. is returned instead.

The following recommendations may be used as alternative solutions to this
problem:

- Replacing mVar (inside the parentheses) with 1 exhibits the correct behavior,
  as does removing the outside parentheses.

- Using the ROUND() function may also solve this problem:

        ? ROUND(mVar+(1048575+(mVar/1000)), 5) = 1048576.001

This behavior does not occur in Visual FoxPro 3.0.

Additional query words:

======================================================================
Keywords          : kbvfp kbvfp500bug kbvfp600bug 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600
Version           : WINDOWS:5.0,6.0

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