Is there a faster way to sum up an arithmetic sequence of numbers in Python? - 


total = 0 in range(0, upper bound):     total +=

sorry if basic have lot of these , they're taking more room comfortable.

total = sum(range(upper))

or

total = upper * (upper - 1) / 2

the first 1 python, second 1 gauss.

edit: when not starting @ zero:

total = sum(range(lower, upper))

or, again according gauss, same upper , substract same lower:

total = upper * (upper - 1) / 2 - lower * (lower - 1) / 2

if on python 2.x, replace range xrange.


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