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On Fri, 2006-06-09 at 10:56 -0700, Bob Sanders wrote: |
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> If your file system driver is calculating where to place the beginning of a |
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> file or where to link the tail of one record to the head or the following |
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> record, one digit mis-calculation could have a bad consequence. And way, |
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> way back in the bad old PDP-11 days, file systems did use FP. I'd |
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> guess a few modern ones might be using it today. |
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Blocks, offsets, inodes, and pointers (addresses) are all "integers", so |
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why would one use floating point? Anyway, floating point is not allowed |
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in the Linux kernel, and drivers are part of the kernel. |
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> |
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> |
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> Also, most financial transactions require a minimum of 4 digits to the right |
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> of the decimal place. Again, a single digit error can cause some folks to |
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> get very, very upset. |
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http://en.wikipedia.org/wiki/Floating_point#Accuracy.2C_and_misconceptions_thereof |
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"...financial software tends not to use a binary floating-point number |
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representation. The "decimal" data type of the C# and Java programming |
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languages, and the IEEE 854 standard, are designed to avoid the problems |
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of binary floating point, and make the arithmetic always behave as |
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expected when numbers are printed in decimal." |
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|
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--- Vladimir |
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|
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-- |
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Vladimir G. Ivanovic <vgivanovic@×××××××.net> |
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-- |
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gentoo-amd64@g.o mailing list |
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