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Why not 1*(0.5-0.4-0.1) = 0?
Message
De
07/01/2005 09:16:06
Hilmar Zonneveld
Independent Consultant
Cochabamba, Bolivie
 
 
À
07/01/2005 03:31:06
Information générale
Forum:
Visual FoxPro
Catégorie:
COM/DCOM et OLE Automation
Versions des environnements
Database:
MS SQL Server
Divers
Thread ID:
00974881
Message ID:
00975063
Vues:
40
>There is some mis-information about BCD & packed decimals. I don't know about mini/mainframe architecture. But in PC, the name is "Binary Coded Decimals" or BCD. There are two types of it, "unpacked BCD" & "packed BCD".
>
>Unpacked BCD only consist of one digit per-byte. The lo-byte is for the digit (unsigned), the hi-byte is for other purposes.
>Packed BCD is two digit per byte, one for each nibble (the lo-byte and the hi-byte). The leftmost digit is for sign.

You are right; BCD can be either packed or unpacked. I had quite forgotten about the details, since I never used them in actual practice.

So, for calculations that are 100% accurate (at least for plus and minus), you have to use BCD - it doesn't matter so much whether it is packed or not.

>Btw, CONGRATULATIONS for you! :-))))

Thanks.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
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