On: Wed, 13 Jan 2010 19:49:00 -0800, Michael Berkowitz
<[log in to unmask]> wrote:

> Maybe someone can explain what exactly is the point of an data
> format that is only sort of correct, some of the time.  What
> advantage does/did real have over integer, decimal and packed
> numeric types that seems to have been worth the stupid headache
> it seems to be

In days of old, when programmers were bold, and disk arrays had not
been invented .  .  .

An R2 takes 4 bytes (32 bits) and has 6.9 digits of precision, an R4
8 bytes (64 bits) and has 16.5 digits of precision.  The 2 and 4
suffex comes from the days when an addressable memory word was two
bytes (16 bits) in length. An R2 took teo words, and R4 took four.

On a computer system with a maximum memory size measured in
kilobytes, where a very large disk drive might be only 20 Mbytes,
and paper tape was a viable storage option, storing really big
numbers with such economy was, shall we say, deemed useful.

Regards,





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