Re: [PD-dev] [PATCH] Avoid crash in vd~ for nan/inf input values

On Tue, Sep 10, 2013 at 8:40 PM, Claude Heiland-Allen claude@mathr.co.uk wrote:

Hi Kjetil,

In my own code I tend to exploit the incomparibility of NaN.

Instead of:

if (x < lo) x = lo; if (x > hi) x = hi;

I write:

if (! (x >= lo)) x = lo; if (! (x <= hi)) x = hi;

As any comparison with NaN gives false, the first version will pass NaN through unchanged, but the second version will replace NaN with lo. Behaviour with finite values and +/-Infinity should remain the same as the first version.

Hi Claude,

That is a nice solution, but is

" if (! (x >= lo)) x = lo; if (! (x <= hi)) x = hi; "

reallly faster than

" if(!isfinite(x)) x = 0.0f; if (x < lo) x = lo; if (x > hi) x = hi; "

?

If not, the second option is much clearer.