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## Re: mod and using large numbers has strange effects:

**From**: |
Gordon Haverland |

**Subject**: |
Re: mod and using large numbers has strange effects: |

**Date**: |
Thu, 12 Oct 2017 15:38:15 -0700 |

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