http://blog.gmane.org/gmane.comp.python.tutor hourly 1 1901-01-01T00:00+00:00 http://gmane.org/img/gmane-25t.png http://gmane.org http://comments.gmane.org/gmane.comp.python.tutor/81834 <pre>I thought tuples were immutable but it seems you can swap them, so I'm confused: a,b = 5,8 print a # result 5 a,b = b,a print a # result 8, so they swapped # but if I test the type of a,b I get a tuple testit = a,b print type(testit) #comes out as a tuple print testit, # result is (8,5) # So how am I swapping elements of a tuple when a tuple is immutable? #t rying so change a tuple since I just did it testit[1] = 14 #program crashes - *TypeError: 'tuple' object does not support item assignment *so the tuple I just changed is indeed immutable </pre> Jim Mooney 2013-05-25T18:56:51 http://comments.gmane.org/gmane.comp.python.tutor/81826 <pre>Gents, thank you all for your help. One of you guys asked me to try out your suggestions and then tell you how it goes. Here we go! First, let me recap briefly what the expected outcome of my program was and which difficulties I encountered at the beginning. I was writing a program in Python 3.3.0 which flips a coin 10 x times and then counts the number of heads and tails. It obviously did something else than I intended: import random print (""" This program flips a coin 10 times. It then counts the number of heads and tails. """) flips = 0 heads = 0 tails = 0 while flips &lt; 10: flips = flips + 1 if random.randint(1,2) == 1: heads = heads + 1 print("We've got " + str(heads) + " heads here." if random.randint(1,2) == 2: tails = tails + 1 print("We've got " + str(tails) + " tails here.") This is what I got as output: This program flips a coin 10 times. It then counts the number of heads and tails. We've got 1 tails here. We've got 1 heads here. We've got 2 t</pre> Rafael Knuth 2013-05-25T09:25:13 http://comments.gmane.org/gmane.comp.python.tutor/81825 <pre>Hi,i am JiangtaoSheng!! _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> jiangtao sheng 2013-05-25T06:34:58 http://comments.gmane.org/gmane.comp.python.tutor/81794 <pre>Hello, I am writing a program in Python 3.3.0 which flips a coin 10 x times and then counts the number of heads and tails. It obviously does something else than I intended, and I am wondering what I did wrong: import random print (""" This program flips a coin 10 times. It then counts the number of heads and tails. """) flips = 0 heads = 0 tails = 0 while flips &lt; 10: flips = flips + 1 if random.randint(1,2) == 1: heads = heads + 1 print("We've got " + str(heads) + " heads here." if random.randint(1,2) == 2: tails = tails + 1 print("We've got " + str(tails) + " tails here.") This is what I get as output: This program flips a coin 10 times. It then counts the number of heads and tails. We've got 1 tails here. We've got 1 heads here. We've got 2 tails here. We've got 2 heads here. We've got 3 tails here. We've got 3 heads here. We've got 4 tails here. We've got 5 tails here. We've got 4 heads here. We've got 6 tails here. We've got 7 tai</pre> Rafael Knuth 2013-05-24T11:01:55 http://comments.gmane.org/gmane.comp.python.tutor/81791 <pre>I keep needing random lists of integers for trying things, so I wrote a small prog I'll import as randlist. The user enters the length and max val, but then I want the actual data name of the random list created, to be list_(length entered)_(max value entered) as an easy mnemonic. I got as far as making the list, but my brain is fozzled on changing the numbers entered into part of a data name. Feels like I have to go outside the program to do it: import random random.seed listparameters = raw_input('\nEnter two numbers, space separated, for the length and largest value of a zero-starting random list, which can be used as variable name: randlist.list_len_max , where len is the list length you entered, and max is the largest value\n') listargs = listparameters.split() rlist = [] length = int(listargs[0]) maxval = int(listargs[1]) for r in range(0,length): rlist.append(random.randint(0,maxval)) listlenmax = 'list' + '_' + str(length) + '_' + str(maxval) # just the name of a string, not the data n</pre> Jim Mooney 2013-05-24T02:39:33 http://comments.gmane.org/gmane.comp.python.tutor/81785 <pre>I guess I'm understanding that, in Python, if something belongs to a type, must also be a value. I guess I'm understanding that the reason why 9 is considered a value, is since it's a normal form*,* an element of the system that cannot be rewritten and reduced any further. I also guess I'm understanding that the same goes somehow for the letter A for example, since it cannot be rewritten or reduced any further, so it's a value too. type('A') &lt;type 'str'&gt; The question is, in order to understand: does this apostrophes thing has a more profound reason to be attached to the letters or it's just a conventional way to set a difference between letters and numbers? Do I must observe this apostrophes thing like the symbol of the type itself inside which one can put any character, setting it as type str? _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Citizen Kant 2013-05-23T19:57:03 http://comments.gmane.org/gmane.comp.python.tutor/81781 <pre>I am asked to present text in different ways by using quotes in strings. for example: print("Program "Game Over" 2.0") print("same", "message", "as before") print("just",         "a bit",         "bigger") print("Here", end=" ") print("it is...") print(           """     """ ) I can't however seem to input the text GAME OVER in giant text as it says in the book. Any help for this would be appreciated. -Mitch Stevens_______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Andrew Triplett 2013-05-23T17:31:44 http://comments.gmane.org/gmane.comp.python.tutor/81780 <pre>Hi, I have Mac OS X 10.7.5 and would like to install &lt; = python 2.3 on it. I need it as one of the s/w I would like to try is based on an older version and does not seem to work with the new ones. I am not sure if the s/w is wrong (doesn't seem like it) or is it really the python version that is messing it up. I tried 2.4 (using mac ports) but thats not it so I want to go further back but I cannot do it with fink or mac ports. Any other suggestions ? I tried to install using a tar file but that gave errors. I am sorry for the dumb question. Thank you for the help _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Robert R 2013-05-23T16:58:18 http://comments.gmane.org/gmane.comp.python.tutor/81761 <pre>I made a simple ear frequency-tester, but I don't want it to go on forever, so I tried stopping it when I pressed a key, as below, but that doesn't work. I did check out keyboard interrupts but they seem unnecessarily complex just to stop a program. I'm not passing keys. Is there something simple I'm missing? import winsound try: for freq in range(100,32000,100): winsound.Beep(freq, 1000) except KeyboardInterrupt: pass </pre> Jim Mooney 2013-05-22T19:47:17 http://comments.gmane.org/gmane.comp.python.tutor/81756 <pre>Does anybody know if there's a Python method that gives or stores the complete list of ascii characters or unicode characters? The list of every single character available would be perfect. Thanks. _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Citizen Kant 2013-05-22T18:14:55 http://comments.gmane.org/gmane.comp.python.tutor/81751 <pre> Then am I right to assume that rather than put in error statements I barely understand at this point, the best thing would be to work the hell out of the program in hope of seeing an error? Does Python have something that would do this automatically since I can't see running a program a hundred times by hand? Mainly, I'm just learning all this stuff for future reference. I really doubt I'll need to use nose to find errors in twenty-line programs. Print, assert, and staring at it for a long time should be enough for now - and the Wing debugger now and then. From the varied replies so far, it sounds to me that debugging is more of an art than a science. So far the books I've looked at just mention the basics but don't get into the philosophy of when and how. Jim _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Jim Mooney 2013-05-22T16:27:59 http://comments.gmane.org/gmane.comp.python.tutor/81732 <pre>Hi everyone. I'm stuck on a problem while developing a small tool for Maya. Basically, I have a folder with some filenames in it which have been returned by os.listdir(). These filenames look something like... apple_d.jpg apple_si.jpg apple_sg.jpg box_d.jpg box_si.jpg pumpkin_d.jpg Right now, I'm using os.listdir to get the filenames, and then each filename becomes a selectable option in an option menu in maya. The code is... objects = os.listdir(dir) for object in objects: cmds.menuItem(label = object, parent = "objectMenu") My problem is that I don't want duplicates of the same object in the menu and I also want to truncate everything past and including the underscore. So for eg, if my filenames are the same as the example above, I want to change the list so I have this instead... apple box pumpkin I have tried splitting the filenames, but so far haven't had any luck. for object in objects: sorted(set(object.split('_', 1)[0])) cmds.menuItem(label = object, pare</pre> Stuart Tozer 2013-05-22T07:49:07 http://comments.gmane.org/gmane.comp.python.tutor/81727 <pre>I'm looking at Try..Except Try: &lt;some statements&gt; Except SomethingError as err: &lt;other statements&gt; The list of error statements is huge. How do I know which error statement to put in place of SomethingError (or multiple errors for that matter)? Or is it best to just leave SomethingError blank until I know more? ( I have an asymptotic learning curve, so I go off on a lot of confused tangents, but I find it makes things go a lot faster after a certain point.) </pre> Jim Mooney 2013-05-22T05:46:06 http://comments.gmane.org/gmane.comp.python.tutor/81726 <pre>I am on chapter two for Python Programming working on the challenges and the question is: 1. Create a list of legal and illegal variable names. Describe why each is either legal or illegal. Next, create a list of "good" and "bad" legal variable names. Describe why each is either a good or bad choice for a variable name. Can you help me solve this problem? _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Andrew Triplett 2013-05-22T05:02:59 http://comments.gmane.org/gmane.comp.python.tutor/81720 <pre>Okay, why is nose saying this run is OK when I purposely screwed it up? import nose def stand_and_deliver(): return 52 def stupid_error(): '''This is my stupid error''' assert stand_and_deliver() == 17 if __name__ == '__main__': nose.runmodule() nose result: Ran 0 tests in 0.000s OK </pre> Jim Mooney 2013-05-22T00:25:37 http://comments.gmane.org/gmane.comp.python.tutor/81719 <pre>I'm trying a nose test on a simple prog. Once I got past the huge traceback in Wing that made me think nose didn't work I realized the prog tested okay. But I noticed at the end of the traceback nose says this: "c:\Python27\Lib\site-packages\nose-1.3.0-py2.7.egg\nose\core.py", line 200, in runTests sys.exit(not self.success) SystemExit: False As i said, nose works and says Okay on the asserts (or not if I give things a bad value). I was just wondering what they SystemExit: False meant, or is that standard? Jim "When I got to high school I realized my name would always present problems." --Dick Hertz _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Jim Mooney 2013-05-22T00:09:33 http://comments.gmane.org/gmane.comp.python.tutor/81718 <pre>Okay. Since I first joined this list I have played around (as time permitted) with these editors/IDEs: PyCharm, Eclipse with PyDev, Notepad++, Emacs, IDLE, PyScripter, IdleX, Sublime Text, and possibly others. Of course, I have far from mastered any of them, but I think that I have a sense of what each is capable of plus an idea of their quirks/bugs. I have found that I do not entirely like any of them. I suppose that is normal. Of the above list I like Notepad++, PyCharm and Emacs the best. I have decided to eliminate Notepad++ due to it being tied entirely to Windows and that it does not have the power of Emacs. I liked PyCharm enough that when a special Earth Day sale came out, I purchased a license for it. Eventually, I think that I will gravitate to this if I start creating truly large projects, but I cannot use it at work. And it seems to be overkill for just beginning in Python. And I don't like the idea of creating a project for what amounts to one-off scripts. So I am led to Emacs. I like the abili</pre> boB Stepp 2013-05-21T18:18:43 http://comments.gmane.org/gmane.comp.python.tutor/81716 <pre>Hi there Tutor folks I need your help with a modified version of the subset sum problem [ http://en.wikipedia.org/wiki/Subset_sum_problem]. The problem i am facing is a bit hard to describe (as most complex problem always are :D ), so please bear with my longish articulation :) Here it goes : After scrubbing some input data, i have two lists 'minutes' (elements are positive integers) &amp; 'names' (elements are strings). They are the exact same length and each element of one corresponds exactly with the respective element of the other. The elements in the minutes list are not unique; a sample list is : minutes = [60, 45, 30, 45, 45, 5, 60, 45, 30, 30, 45, 60, 60, 45, 30, 30, 60, 30, 30 ] names = ['abc', 'ghi', 'jkl', 'def', 'zab', 'wux', ........... ] Now i need to pick some elements from the 'minutes' list (i.e. a subset of minutes) which add up to a certain sum ('target_sum1'). I have to then do some processing with the *respective elements from the 'names' list, corresponding to, the elements i just pic</pre> spiff007 2013-05-21T15:52:35 http://comments.gmane.org/gmane.comp.python.tutor/81708 <pre>If I make a package called jimlib with __init__.py in it, and a program called bark.py in it, and even put it in site packages, I still have to import the program with import jimlib.bark But I noticed that the pygraphics package is in site packages, and has media.py in it, and all I have to do with that is import media, without qualifying it with pygraphics, as in import pygraphics.media Why don't I have to drill down for media.py as I do with jimlib? </pre> Jim Mooney 2013-05-21T01:43:04 http://comments.gmane.org/gmane.comp.python.tutor/81706 <pre>Hi python folks, I have a list of lists that looks something like this: tst = [ [], ['test'], ['t1', 't2'], ['t1', 't1', 't2'] ] I want to change the empty sets to a blank string, i.e., '' and the lists with repeat values to the unique set of values. So I have done the following: if len(t) == 0: tst.__setitem__(tst.index(t), '') else: tst.__setitem__(tst.index(t), set(t)) What I get in return is ['', set(['test']), set(['t2', 't1']), set(['t2', 't1'])] The empty list is fine but the other lists seem to be expressions rather than values. What do I need to do to simply get the values back liike the following? ['', ['test'], ['t2', 't1'], ['t2', 't1']] Thanks, Bob -------------------------------------------------------------------------------- NOTICE: Morgan Stanley is not acting as a municipal advisor and the opinions or views contained herein are not intended to be, and do not constitute, advice within the meaning of Section 975 of the Dodd-Frank Wall Street Reform and Consumer </pre> Treder, Robert 2013-05-20T22:49:08 http://comments.gmane.org/gmane.comp.python.tutor/81697 <pre>Hello, I wrote a simple program, and I was expecting that I would get 100 different random numbers. Instead, I am getting 100 times exactly the same random number. Can anyone advise how I should alter my program? Thank you! All the best, Rafael PS. I am using Python 3.3.0 print (""" This game will return 100 random numbers between 1 and 100. """) import random Count = 0 Random_Number = random.randint(1, 100) while Count &lt;= 100: print (Random_Number) Count = Count + 1 _______________________________________________ Tutor maillist - Tutor&lt; at &gt;python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor </pre> Rafael Knuth 2013-05-20T16:31:47 Search the mailing list at Gmane query http://search.gmane.org/?group=$group=gmane.comp.python.tutor