How does one distribute Tkinter or Qt GUI apps Developed in Python
I watched one training video that discussed Python and Tkinter. Like many similar tutorials from online training sites, I was left scratching my head. What seems to be blatantly missing is how this would be distributed. In the first mentioned tutorial from Lynda.com the Tkinter app was related to a web page. However, the browser cannot run Python Bytecode or Python Scripts. Surely, one is going to want to create GUI apps for users that are not Python Developers. I would not think to ask someone to install Python on their system and make sure it is added to the path. Maybe it is not so hard for the non-technical, average users. I would want to package in some way so that when launched, it installs whatever is needed on the end user's computer. How is this done? Are there common practices for this? Thanks, Bruce -- https://mail.python.org/mailman/listinfo/python-list
Re: Prob. Code Downloaded for Programming the Semantic Web (python code)
On Friday, July 25, 2014 9:28:32 PM UTC-4, Steven D'Aprano wrote: On Fri, 25 Jul 2014 17:06:17 -0700, Bruce Whealton wrote: Steven, See below please. The explanation did help. OK, Eclipse with PyDev doesn't like this first line, with the function: def add(self, (sub, pred, obj)): In Python 2, you could include parenthesised parameters inside function declarations as above. That is effectively a short cut for this version, where you collect a single argument and then expand it into three variables: def add(self, sub_pred_obj): sub, pred, obj = sub_pred_obj I setup Eclipse to use python 2.7.x and tried to run this and it just gave an error on line 9 where the def add function is declared. It just says invalid syntax and points at the parentheses that are in the function definition def add(self, (subj, pred, obj)): So, from what you said, and others, it seems like this should have worked but eclipse would not run it. I could try to load it into IDLE. In Python 3, that functionality was dropped and is no longer allowed. Now you have to use the longer form. I'm not sure I follow what the longer method is. Can you explain that more, please. [...] There are other places where I thought that there were too many parentheses and I tried removing one set of them. For example this snippet here: def remove(self, (sub, pred, obj)): Remove a triple pattern from the graph. triples = list(self.triples((sub, pred, obj))) Firstly, the remove method expects to take a *single* argument (remember that self is automatically provided by Python) which is then automatically expanded into three variables sub, pred, obj. So you have to call it with a list or tuple of three items (or even a string of length exactly 3). Then, having split this list or tuple into three items, it then joins them back again into a tuple: (sub, pred, obj) passes that tuple to the triples method: self.triples((sub, pred, obj)) (not shown, but presumably it uses the same parenthesised parameter trick), and then converts whatever triples returns into a list: The full code listing should be available in the code paste link that I included. list(self.triples((sub, pred, obj))) that list then being bound to the name triples. Thanks, the explanation helped, Bruce -- https://mail.python.org/mailman/listinfo/python-list
Re: Prob. Code Downloaded for Programming the Semantic Web (python code)
On Friday, July 25, 2014 11:25:15 PM UTC-4, Chris Angelico wrote: On Sat, Jul 26, 2014 at 10:06 AM, Bruce Whealton Chris, In response to your comments below, I'm comfortable changing this to use python 3. As others have said, this is something that changed in Python 3. So you have two parts to the problem: firstly, your code is bound to Python 2 by a triviality, and secondly, Eclipse is complaining about it. But a better solution, IMO, would be to avoid that implicit tuple unpacking. It's not a particularly clear feature, and I'm not sorry it's gone from Py3. The simplest way to change it is to just move it into the body: OK, that makes sense. So, I cut out the Alternatively... suggestion you made. def add(self, args): sub, pred, obj = args # rest of code as before Preferably with a better name than 'args'. Yes, I could call it triples. triples = list(self.triples((sub, pred, obj))) Are the two sets parentheses needed after self.triples? That syntax is confusing to me. It seems that it should be triples = list(self.triples(sub, pred, obj)) No, that's correct. The extra parens force that triple to be a single tuple of three items, rather than three separate arguments. Here's a simpler example: lst = [] lst.append(1,2,3) Traceback (most recent call last): File pyshell#25, line 1, in module lst.append(1,2,3) TypeError: append() takes exactly one argument (3 given) lst.append((1,2,3)) addme = 4,5,6 lst.append(addme) lst [(1, 2, 3), (4, 5, 6)] This is helpful and makes sense... clarifies it for me. The list append method wants one argument, and appends that argument to the list. Syntactically, the comma has multiple meanings; when I assign 4,5,6 to a single name, it makes a tuple, but in a function call, it separates args in the list. I don't see why the triples() function should be given a single argument, though; all it does is immediately unpack it. It'd be better to just remove the parens and have separate args: triples = list(self.triples(sub, pred, obj)) I didn't see the above in the code... Is this something I would need to add and if so, where? def triples(self, sub, pred, obj): While I'm looking at the code, a few other comments. I don't know how much of this is your code and how much came straight from the book, but either way, don't take this as criticism, but just as suggestions for ways to get more out of Python. So far it is just from the book, and just serves as an example... It is also a few years old, having been published in 2009. Inside remove(), you call a generator (triples() uses yield to return multiple values), then construct a list, and then iterate exactly once over that list. Much more efficient and clean to iterate directly over what triples() returns, as in save(); that's what generators are good for. In triples(), the code is deeply nested and repetitive. I don't know if there's a way to truly solve that, but I would be inclined to flatten it out a bit; maybe check for just one presence, to pick your index, and then merge some of the code that iterates over an index. Not sure though. I would have to get a better understanding of this. (Also: It's conventional to use is not None rather than != None to test for singletons. It's possible for something to be equal to None without actually being None.) I would recommend moving to Python 3, if you can. Among other benefits, the Py3 csv module allows you to open a text file rather than opening a binary file and manually encoding/decoding all the parts separately. Alternatively, if you don't need this to be saving and loading another program's files, you could simply use a different file format, which would remove the restrictions (and messes) of the CSV structure. I was curious about why the binary flag was being used. It just made no sense to me. Instead of explicitly putting f.close() at the end of your load and save methods, check out the 'with' statement. It'll guarantee that the file's closed even if you leave early, get an exception, or anything like that. Also, I'd tend to use the .decode() and .encode() methods, rather than the constructors. So here's how I'd write a Py2 load: I would like to see this in python 3 format. def load(self, filename): with open(filename, rb) as f: for sub, pred, obj in csv.reader(f): self.add((sub.decode(UTF-8), pred.decode(UTF-8), obj.decode(UTF-8))) (You might want to break that back out into three more lines, but this parallels save(). If you break this one, you probably want to break save() too.) Hope that helps! ChrisA Thanks, Bruce -- https://mail.python.org/mailman/listinfo/python-list
Re: Prob. Code Downloaded for Programming the Semantic Web (python code)
On Monday, July 28, 2014 11:28:40 AM UTC-4, Steven D'Aprano wrote: On Mon, 28 Jul 2014 03:39:48 -0700, Bruce Whealton wrote: Stephen, I went to my Ubuntu box inside vmware and added a #!/usr/bin/env python2.7 to the top. Then I made the file executable and it ran the code perfectly. First step is to confirm that Eclipse actually is using Python 2.7. Can you get it to run this code instead? Put this in a module, and then run it: import sys print(sys.version) I had both python2.7 and python3.4. I could be less specific with my shebang line but what the heck. I then installed pydev into my eclipse environment within the Ubuntu virtual machine and it ran the program just fine. So, I suspect the extra character was only an issue on Windows. I thought I had it setup to show even hidden characters. Anyway, thanks so much for all the help...everyone. It might be interesting for me to convert this to a module that runs with python 3. Bruce It just says invalid syntax and points at the parentheses that are in the function definition def add(self, (subj, pred, obj)): So, from what you said, and others, it seems like this should have worked but eclipse would not run it. I could try to load it into IDLE. Whenever you have trouble with one IDE, it's good to get a second opinion in another IDE. They might both be buggy, but they're unlikely to both have the same bug. Also, try to run the file directly from the shell, without an IDE. from the system shell (cmd.exe if using Windows, bash or equivalent for Linux), run: python27 /path/to/yourfile.py You'll obviously need to adjust the pathname, possibly even give the full path to the Python executable. [...] In Python 3, that functionality was dropped and is no longer allowed. Now you have to use the longer form. I'm not sure I follow what the longer method is. Can you explain that more, please. I referred to the parenthesised parameter version as a short cut for a method that takes a single argument, then manually expands that argument into three items. Let me show them together to make it more obvious: # Unparenthesised version, with manual step. def add(self, sub_pred_obj): sub, pred, obj = sub_pred_obj do_stuff_with(sub or pred or obj) # Parenthesised shortcut. def add(self, (sub, pred, obj)): do_stuff_with(sub or pred or obj) Both methods take a single argument, which must be a sequence of exactly three values. The second version saves a single line, hence the first version is longer :-) -- Steven -- https://mail.python.org/mailman/listinfo/python-list
Strange Error with pip install.
Hello, I am using Windows 8.1 (I do have a linux box setup with virtualbox also) and I've used python previously but now it is giving me problems whenever I try to install anything from PyPI using pip. The error I get from the command line is Cannot fetch index base URL http://pypi.python.org/simple/ Could not find any downloads that satisfy the requirement... I tried within the MinGW environment setup when I installed Git and was given Git Bash as a console. I also installed Bitnami Django stack and even in that environment, I get that error. I did some Google searches but I seem to only happen when people are trying to install Django. For me it is happening with django and any other pypi installation with pip. Interestingly, as I started trying to get advice with this, in the django chat room - at the time I was trying to get django to work in my Windows environment, someone suggested Vagrant. I started creating some boxes with Vagrant and Puppet, Chef or bash scripts. I had problems with this inside a Windows command prompt. So, I tried it under the MinGW environment I mentioned above, and half the time, when I run Vagrant up, it starts the environment but then it tries to connect using a public key authentication. Sometimes it will just give up and let me run vagrant ssh or use putty. Other times it just times out. One idea I have is to import a VirtualBox box from Bitnami into VirtualBox, their Django stack. Does anyone have any suggestions about this problem I am having using pip install somepackage inside Windows (Windows 8, if that matters)? Thanks in advance, Bruce -- https://mail.python.org/mailman/listinfo/python-list
Prob. Code Downloaded for Programming the Semantic Web (python code)
Hello all, I downloaded some code accompanying the book Programming the Semantic Web. This question is not Semantic Web related and I doubt that one needs to know anything about the Semantic Web to help me with this. It's the first code sample in the book, I'm embarrassed to say. I have the code shared here (just one file, not the majority of the book or anything): http://pastebin.com/e870vjYK OK, Eclipse with PyDev doesn't like this first line, with the function: def add(self, (sub, pred, obj)): It complains about the parentheses just before sub. Simply removing them just moves me down to another error. I did try using python 3.x (3.4 to be specific), which meant changing print statements to function calls. Of course, that didn't fix the errors I was mentioning. The text uses python 2.7.x. There are other places where I thought that there were too many parentheses and I tried removing one set of them. For example this snippet here: def remove(self, (sub, pred, obj)): Remove a triple pattern from the graph. triples = list(self.triples((sub, pred, obj))) Are the two sets parentheses needed after self.triples? That syntax is confusing to me. It seems that it should be triples = list(self.triples(sub, pred, obj)) The full listing is here: http://pastebin.com/e870vjYK I agree with the authors that python is a fun and easy language to use, thus it is strange that I am getting stuck here. Thanks, Bruce -- https://mail.python.org/mailman/listinfo/python-list
Re: Newbie help - Programming the Semantic Web with Python
Hello, So, regarding the path that python uses to find modules, I read the link that you sent. Suppose, I open IDLE and start an interactive session. That would mean the input script location is wherever python is installed, correct? I did add an environment variable PYTHONPATH which did not even exist when I first installed Python. I figured I would want to have a directory where I could store modules that might interest me. I might want to expand that into a package style path later. Now, if I was going to create an application to run on the web, I guess those included modules would have to get compiled with the rest of the code for it to work, right? Bruce -Original Message- From: Chris Angelico Sent: Saturday, July 09, 2011 10:10 PM To: python-list@python.org Subject: Re: Newbie help - Programming the Semantic Web with Python On Sun, Jul 10, 2011 at 11:32 AM, Bruce Whealton br...@whealton.info wrote: problem with is this line: def add(self, (sub, pred, obj)): I think the problem is with the parentheses before the sub. I removed those and that seemed to fix that error or make it go away. I don’t remember how I figured that out, It should be on the Errata page for sure. Then it has a problem with this line: print list(g.triples((None, None, None))) If I was using python 3, it would require () around the thing that is going to be printed, right? Maybe python 2.7 doesn’t like this line for the same reason. The issue there is with tuple unpacking. To match the older syntax, don't touch the call, but change the definition thus: def add(self, args): (sub, pred, obj)=args Or, of course, simply list the arguments directly, rather than in a tuple; but that requires changing every call (if it's a small program that may not be a problem). You're right about needing parentheses around the print() call; in Python 2 it's a statement, but in Python 3, print is a function like any other. Regarding the module search path, this may help: http://docs.python.org/dev/tutorial/modules.html#the-module-search-path Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Newbie help - Programming the Semantic Web with Python
This didn't seem to work either. I was getting errors the number of arguments expected being two, when I changed to def add (self, args): I seem to remember that if I removed the parentheses around sub, pred, obj, it worked. I thought that was how it worked. What is strange is that this is not reported as an error on the books page. So, it should have worked as is with either Python 2.7, which I have installed or Python 3.0 which I also have installed. So, it seems like it would have worked as is for one of the versions of Python, but it doesn't seem to work that way. I'll paste a link to where the code exists. Could someone help me figure it out please. The code is here on the site: http://semprog.com/content/the-book/ I wonder if I can also try it out from the IDLE interactive session. Thanks, Bruce On Sun, Jul 10, 2011 at 11:32 AM, Bruce Whealton br...@whealton.info wrote: problem with is this line: def add(self, (sub, pred, obj)): I think the problem is with the parentheses before the sub. I removed those and that seemed to fix that error or make it go away. I don’t remember how I figured that out, It should be on the Errata page for sure. Then it has a problem with this line: print list(g.triples((None, None, None))) If I was using python 3, it would require () around the thing that is going to be printed, right? Maybe python 2.7 doesn’t like this line for the same reason. The issue there is with tuple unpacking. To match the older syntax, don't touch the call, but change the definition thus: def add(self, args): (sub, pred, obj)=args Or, of course, simply list the arguments directly, rather than in a tuple; but that requires changing every call (if it's a small program that may not be a problem). You're right about needing parentheses around the print() call; in Python 2 it's a statement, but in Python 3, print is a function like any other. Regarding the module search path, this may help: http://docs.python.org/dev/tutorial/modules.html#the-module-search-path Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Newbie help - Programming the Semantic Web with Python
Thanks for the tips. I actually had done some studies with Python, mainly Python 3, back about 6 months ago and over a period of a few months. I didn't write a great deal of programs though, at the time. I got away from it in a while and I didn't want to go back to step one of being like a total beginner. There are so many things I try to keep up with as a Web Developer and coder and trying to expand my skills. Unfortunately, I don't do well with picking a focus. I remember reading through this long reference manual, called Learning Python, while I was on a flight and over a trip. That was without a computer, so I was just reading, which is not the way to learn programming, obviously. I feel the many concepts will come back to me fast. I have another text, called Beginning Python: From Novice to Professional which covers Python 3. This is a bit more practical in orientation. I'm debating whether to jump to the chapters dealing with the web and see what I can do or starting from the beginning. I did look into some online training, tutorials, or the like. The Programming the Semantic Web book uses Python but all the code is included. So, while it won't be a way to learn python, I hope I can get the code to run correctly. In that text, they must be using Python 2.7 because I see print statements and not the print function call. If you know of any good resources for finding python applications on the web, this might be a good way to learn. I don't know if I should look for Python applications, or if I'll have more luck looking for Python Libraries. Thanks, Bruce -Original Message- From: Andrew Berg Sent: Saturday, July 09, 2011 10:44 PM To: comp.lang.python Subject: Re: Newbie help - Programming the Semantic Web with Python On 2011.07.09 08:32 PM, Bruce Whealton wrote: Hello, So, I got this book on Programming the Semantic Web about the same time I started learning Python. The code seems to be developed for python 2.7 and not 3, I believe. If you're going to learn Python 3, I suggest learning from a book that deals with Python 3 (if there's not an updated text for the area you're dealing with, go with something that teaches the basics). Once you have the basics down and you know the common differences, then it will be much easier to learn from a text that's based on Python 2 (you'll stumble a whole lot less when trying to learn from such texts). You'll also find some things in Python 3 that have been added to recent versions of Python 2 that the text may not cover (e.g., the old % string formatting syntax vs. the new format() string method). If I was using python 3, it would require () around the thing that is going to be printed, right? That's not really the right way to think of the print() function. The print statement has some very arbitrary syntax that could cause unexpected behavior if simply put in the print() function. The print function has parameters for optional behavior rather than odd syntax. In the simplest cases, print and print() are extremely similar, but print() has a bunch of functionality that is either difficult/annoying to decipher (for humans, not the interpreter) or simply doesn't exist in print. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Newbie help - Programming the Semantic Web with Python
Hello, So, I got this book on Programming the Semantic Web about the same time I started learning Python. The code seems to be developed for python 2.7 and not 3, I believe. The code is here: http://semprog.com/content/the-book/ I tried to run simpletriple.py from inside eclipse with PYDEV. The first thing it has a problem with is this line: def add(self, (sub, pred, obj)): I think the problem is with the parentheses before the sub. I removed those and that seemed to fix that error or make it go away. I don’t remember how I figured that out, It should be on the Errata page for sure. Then it has a problem with this line: print list(g.triples((None, None, None))) If I was using python 3, it would require () around the thing that is going to be printed, right? Maybe python 2.7 doesn’t like this line for the same reason. The book suggests that from IDLE, I can just use from simplegraph import SimpleGraph That means it is going to look for a file named simplegraph.py but where will it be looking? I guess I would have to have it in the same folder as the python interpreter or one of the PATH directories, right? Thanks, Bruce ++ Bruce Whealton, Owner Future Wave Designs FOAF: http://whealton.info/BruceWhealtonJr/foaf.rdf Vcard: http://whealton.info/BruceWhealtonJr/brucewhealtonvcard.html Web Design and Development http://FutureWaveDesigns.com http://futurewavedesigns.com/wordpress/ Web Technology wiki: http://futurewavedesigns.com/w/ ++ wlEmoticon-smile[1].png-- http://mail.python.org/mailman/listinfo/python-list
Clarification of notation
Hello all, I recently started learning python. I am a bit thrown by a certain notation that I see. I was watching a training course on lynda.com and this notation was not presented. For lists, when would you use what appears to be nested lists, like: [[], [], []] a list of lists? Would you, and could you combine a dictionary with a list in this fashion? Next, from the documentation I see and this is just an example (this kind of notation is seen elsewhere in the documentation: str.count(sub[, start[, end]]) This particular example is from the string methods. Is this a nesting of two lists inside a a third list? I know that it would suggest that some of the arguments are optional, so perhaps if there are 2 items the first is the sub, and the second is start? Or did I read that backwards? Thanks, Bruce -- http://mail.python.org/mailman/listinfo/python-list
