Xah Lee wrote:
> I think it would be a improvement for the built-in range() so that step
> needs not be an integer. [...]
>
> Range( 5, 7, 0.3); # returns [5, 5.3, 5.6, 5.9, 6.2, 6.5, 6.8]
This may not return what you expect it to return.
For example let's use a naive implementation like this:
def Range(start, stop, step):
values = []
while start < stop:
values.append(start)
start += step
return values
The result is:
>>> Range(5, 7, 0.3)
[5, 5.2999999999999998, 5.5999999999999996, 5.8999999999999995,
6.1999999999999993, 6.4999999999999991, 6.7999999999999989]
Worse: Range(5, 7.1, 0.3) would return 8 values, not 7 as expected from e.g.
range(50, 71, 3).
Welcome to the interesting world of floating point numbers.
Harald
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