On Tue, Nov 7, 2017, 10:55 PM Alok Gandhi <[email protected]> wrote:
> Being really picky, please do not use lambda in a variable (PEP8) - > > Always use a def statement instead of an assignment statement that binds a > lambda expression directly to an identifier. > > Yes: > > def f(x): return 2*x > > No: > > f = lambda x: 2*x > > The first form means that the name of the resulting function object is > specifically 'f' instead of the generic '<lambda>'. This is more useful for > tracebacks and string representations in general. The use of the assignment > statement eliminates the sole benefit a lambda expression can offer over an > explicit def statement (i.e. that it can be embedded inside a larger > expression) > Thanks for the suggestion, Alok. > On Tue, Nov 7, 2017 at 2:25 AM, Marcus Ottosson <[email protected]> > wrote: > >> Ooo, I’ve been waiting for a reason to use this! >> >> # import sys# maxint = sys.maxint >> >> by_nonzero = lambda i: i or float("inf") >> >> l = [4,0,8,0,0,2,1,-5] >> l.sort(key=by_nonzero)print l# [-5, 1, 2, 4, 8, 0, 0, 0] >> >> >> >> On 6 November 2017 at 18:47, Justin Israel <[email protected]> >> wrote: >> >>> >>> >>> On Tue, Nov 7, 2017, 4:58 AM Balazs Pataki <[email protected]> >>> wrote: >>> >>>> You could also try this, which is a bit more pythonic, also faster. >>>> >>>> def re_sort(to_sort): >>>>> # we need those zeroes so we check how many of them we have >>>>> nr_of_zeroes = to_sort.count(0) >>>>> # list comprehension that gets rid of zeroes >>>>> filtered = [item for item in to_sort if item != 0] >>>>> # we append together the filtered part and inplace add a list of >>>>> zeroes of length nr_of_zeroes >>>>> return filtered + [0]*nr_of_zeroes >>>> >>>> >>>> While this has time complexity of O(n), yours is O(n^2), so the longer >>>> your list gets, the worse your performance gets. >>>> >>> >>> I'm not great at big O notation. Is the original solution suggested to >>> be O(n^2) because of the nested remove(i) call within the loop? Would that >>> have a logarithmic complexity instead because the list becomes shorter >>> everytime it finds a 0 and removes it? Otherwise it would not remove at all >>> for nonzero. >>> >>> And then your solution has two O(n) calls (the count and the list comp) >>> so that is O(n) yea? Then you have the memory complexity of needing to >>> allocate temporary lists for the final nonzero and zero lists. >>> >>> Here is one more approach that uses a sort in place. It has both >>> examples depending on whether you want the nonzero numbers sorted or not. >>> >>> >>> by_nonzero = lambda i: 0 if i else 1 >>> >>> l = [4,0,8,0,0,2,1,-5] >>> l.sort(key=by_nonzero) >>> print l >>> # [4, 8, 2, 1, -5, 0, 0, 0] >>> >>> >>> import sys >>> maxint = sys.maxint >>> >>> by_nonzero = lambda i: i or maxint >>> >>> l = [4,0,8,0,0,2,1,-5] >>> l.sort(key=by_nonzero) >>> print l >>> # [-5, 1, 2, 4, 8, 0, 0, 0] >>> >>> >>> >>> >>>> >>>> On Sunday, November 5, 2017 at 3:07:32 PM UTC+1, Virbhadra Gupta wrote: >>>>> >>>>> >>>>> >>>>> i was trying to sort list by only 0 and other Numbers like [2,0,0,4] >>>>> to [2,4,0,0] >>>>> i come up with this code but in this code variable list is changing. i >>>>> am unable to understand why ? >>>>> >>>>> list = [4,0,0,4] >>>>> >>>>> def re_sort(list): >>>>> count=0 >>>>> tmp_list = list >>>>> print list >>>>> for i in list: >>>>> if not i: >>>>> tmp_list.remove(i) >>>>> count+=1 >>>>> print list >>>>> for n in range(count): >>>>> tmp_list.append(0) >>>>> return tmp_list >>>>> re_sort(list) >>>>> >>>>> ************************ >>>>> re_sort(list) >>>>> [4, 0, 0, 4] >>>>> [4, 0, 4] >>>>> # Result: [4, 0, 4, 0] # >>>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Python Programming for Autodesk Maya" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/python_inside_maya/700827e3-cb90-4106-8da4-350e08096dbd%40googlegroups.com >>>> <https://groups.google.com/d/msgid/python_inside_maya/700827e3-cb90-4106-8da4-350e08096dbd%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Python Programming for Autodesk Maya" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA1k7yVorfG_sbf2Pj7%3DG4qo5X-A7vhOO0DQZseu%3DxSGjA%40mail.gmail.com >>> <https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA1k7yVorfG_sbf2Pj7%3DG4qo5X-A7vhOO0DQZseu%3DxSGjA%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Python Programming for Autodesk Maya" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOA8PD%3DAMFtoyMvoQ5J3BT69GWxJotk%3DPk0yG0dh_FvCWw%40mail.gmail.com >> <https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOA8PD%3DAMFtoyMvoQ5J3BT69GWxJotk%3DPk0yG0dh_FvCWw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > > -- > You received this message because you are subscribed to the Google Groups > "Python Programming for Autodesk Maya" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/python_inside_maya/CAPaTLMSrJKG_Vuj5PxmjScOhc_Ly%3Ds2B9KLpBLbY_wy087h6aA%40mail.gmail.com > <https://groups.google.com/d/msgid/python_inside_maya/CAPaTLMSrJKG_Vuj5PxmjScOhc_Ly%3Ds2B9KLpBLbY_wy087h6aA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Python Programming for Autodesk Maya" group. 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