Antoon Pardon <[EMAIL PROTECTED]> writes: > It may be convincing if you only consider natural numbers in > ascending order. Suppose you have the sequence a .. b and you want > the reverse. If you work with included bounds the reverse is just b > .. a. If you use the python convention, things become more > complicated.
It's a tradeoff. The convention used by Python (and Lisp, Java and others) is more convenient for other things. Length of the sequence x[a:b] is simply b-a. Empty sequence is denoted simply with x[a:a], where you would need to use the weird x[a:a-1] with inclusive bounds. Subsequences such as x[a:b] and x[b:c] merge smoothly into x[a:c], making it natural to iterate over subsequences without visiting an element twice. > Another problem is if you are working with floats. Suppose you have > a set of floats. Now you want the subset of numbers that are between > a and b included. If you want to follow the convention that means > you have to find the smallest float that is bigger than b, not a > trivial task. The exact same argument can be used against the other convention: if you are working with inclusive bounds, and you need to represent the subset [a, b), you need to find the largest float that is smaller than b. -- http://mail.python.org/mailman/listinfo/python-list
