Arnaud Delobelle wrote: > On Mar 17, 10:24 pm, "BJörn Lindqvist" <[EMAIL PROTECTED]> wrote: >> Here is an interesting math problem: >> >> You have a number X > 0 and another number Y > 0. The goal is to >> divide X into a list with length Y. Each item in the list is an >> integer. The sum of all integers is X. Each integer is either A or A + >> 1, those should be "evenly distributed." >> >> Example: >> >> 17 // 5 = 3 gives the list [3, 3, 4, 3, 4] >> 16 // 4 = 4 gives the list [4, 4, 4, 4] >> 113 // 50 = 2 gives the list [2, 3, 2, 3, 3, 2, 3, 2, 3, 3, 2, 3, 2, >> 3, 3, 2, 3, 2, 3, 3, 2, 3, 2, 3, 3, 2, 3, 2, 3, 3, 2, 3, 2, 3, 3, 2, >> 3, 2, 3, 3, 2, 3, 2, 3, 3, 2, 3, 2, 3, 3] >> >> This algorithm is used a lot in programming. For example, for >> projecting a line on a pixel display. Your mission, should you choose >> to accept it, is to improve the code given below which is my best >> attempt and make it more succinct and easier to read. Preferably by >> using list comprehensions, map or even reduce.... >> >> def make_slope(distance, parts): >> step = distance / float(parts) >> intstep = int(step) >> floatstep = step - intstep >> >> steps = [] >> acc = 0.0 >> for i in range(parts): >> acc += floatstep >> step = intstep >> if acc > 0.999: >> step += 1 >> acc -= 1.0 >> steps.append(step) >> return steps >> >> # Test code >> distance = 130 >> parts = 50 >> L = make_slope(distance, parts) >> assert(len(L) == parts) >> assert(sum(L) == distance) >> print L >> >> -- >> mvh Björn > > OK then, using list comprehensions. It is more succint, is it easier > to read? > > def slope(dist, parts): > return [(i+1)*dist/parts - i*dist/parts for i in xrange(parts)]
That's awesome, but I sure hope you'd mix in a comment in real code. ;) -- http://mail.python.org/mailman/listinfo/python-list
