Re: Catastrophic Cancellation

[Francesco Potorti`]

>But this particular example is designed specifically for machines
>with 16-bit precision.  If we rewrite the same routine using long
>doubles, which with glibc on Linux has roughly 19-bits,

What do you mean, exactly?

>the problem disappears except for a tiny region around zero.

This is true for any precision.

>                                                  Soon, the gcc
>compiler and glibc will support the float128 data type which will
>provide 32 bits of precision.

Again, what do you mean by "32 bits of precision"?

The precision of Octave's floating point representation is about 16
decimal digits: 
<https://www.cae.wisc.edu/pipermail/help-octave/2008-June/009755.html>

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