Re: mod and using large numbers has strange effects:

[Gordon Haverland]

On Thu, 12 Oct 2017 17:58:59 -0400
RT <address@hidden> wrote:

> >> realmax
> ans = 1.79769313486232e+308
> 
> ​​
> for ii=
> ​0:360
>   z=mod(realmax,ii)
> end
> 
> ​z varies from
> z = Inf
> z =                    0
> z =                    0
> z = 1.99584030953472e+292​
> 
> ​I was expecting z to be between 0​ and 360 what am I doing wrong.

Expecting a reasonable answer.

You have a number, which you may be expecting to be a counting number
(integer) which has 308 decimal places.  If we convert that to base 2,
it will be some huge number of bits.  Octave might be using 8 bytes to
represent a number.  Nowhere near the size you need.

Work with much smaller numbers, and slowly increase them.  Look at how
the error scales with the size of the number.

Gord