Floating point subtraction rounding error (NOT display error)

[Carl Banks]

On Dec 13, 6:20 pm, Keflavich <keflav... at gmail.com> wrote:
> Solved: used round(number,12) in this case for all of the operands of
> my arcsines.  Not pretty, but at least VIM made it easy...
>
> Thanks for the help,
> Adam

I suspect this could even fail in some circumstances.  If it's for
school you're probably covered, but in real world, it would be better
to:

1. Rewrite calculation to avoid arccos and arcsin (using trigonometric
or geometric identities)

2. Clamp it to range [-1.0:1.0].  You can do this in numpy with
numpy.clip().


Carl Banks