Results Differ for Alternate & Coprocessor/Emulator Math

ID: Q36069

5.10 6.00 6.00a 6.00ax 7.00 | 5.10 6.00 6.00a | 1.00

MS-DOS                      | OS/2            | WINDOWS
kbprg

The information in this article applies to:

SUMMARY

The coprocessor/emulator math library and the alternate math library may produce different results for floating-point calculations.

MORE INFORMATION

When an application uses the coprocessor to perform floating-point arithmetic, it pushes all values onto the coprocessor stack. The stack holds only 10-byte real values. Therefore, any 4-byte or 8-byte real (double) values are expanded to 10-byte reals before any operations are performed. The emulator library performs the same expansion. The results are converted back to a 4-byte or 8-byte real value as appropriate.

The alternate math library performs calculations directly using 4-byte or 8-byte real values which can result in less calculation precision than that available with the coprocessor/emulator math library.

Additional reference words: kbinf 5.10 6.00 6.00a 6.00ax 7.00 1.00 KBCategory: kbprg KBSubcategory: CRTIss Keywords : kb16bitonly

Last Reviewed: July 18, 1997