Newbie: strange int() behaviour

[Raymond Hettinger]

> My very first python script calculates a value for a given number, prints
> out a number of line conisting of stars (half the number) and the value
> itself.
>
> Out of some strange reason it looks like 100 / 2 is in one case 49. Why?
>
> The main loop:
> for i in range (80,100,1):
>     val = fuz.process("temp",i,"speed")

Add this line:
       print val        # Will reveal that fuz.process returns
                            #  slightly less than 100.0000 for i=87

>     half = val /2

Here is the problem.
Val is a floating point number slightly less than 100.0
and the / 2 gives floor division, truncating to 49.
Try this line instead:

       half = round(val / 2.0, 3)

>     length = int(half)
>     stars= length * "*"
>     print "%s %s (%f) stars: %s" % (i,stars,val,length)


Raymond Hettinger