🌐 Mailman 3 August 2013 - Tutor - python.org

Scripting Calligra sheets with Python
by Jim Byrnes Jan. 31, 2022

Jan. 31, 2022

I am trying to script Calligra Sheets (formerly KSpread) with python. I have gotten some of the included example scripts to run so I know python scripting is running. I found the following snippet on their website: import KSpread sheet = KSpread.view().sheet() # swap text of B5 and C6 t1 = sheet.text("B5") t2 = sheet.text(6,3) sheet.setText("B5", t2) sheet.setText(6, 3, t1) # swap value of D7 and E8 v1 = sheet.value("D7") v2 = sheet.value(8,5) sheet.setValue("D7", v2) sheet.setValue(8, 5, v1) Error: 'str' object has no attribute 'text' File "file:///usr/share/kde4/apps/sheets/scripts/extensions/myswap.py", line 4, in <module> This error message appeared in a dialog box. I've taught myself some Python but I don't understand what is happening here. Shouldn't t1 be a sheet object? What would cause it to be a str instead? Thanks, Jim

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Wave module
by Alex Krycek Feb. 12, 2015

Feb. 12, 2015

Hello, I'm trying to join two .wav files with the wave module. But when I try to use wave.open(filename, "rb") I receive the following error: Traceback (most recent call last): File "<stdin>", line 1, in <module> File "F:\PortablePython1.0\lib\wave.py", line 483, in open return Wave_read(f) File "F:\PortablePython1.0\lib\wave.py", line 162, in __init__ self.initfp(f) File "F:\PortablePython1.0\lib\wave.py", line 143, in initfp self._read_fmt_chunk(chunk) File "F:\PortablePython1.0\lib\wave.py", line 264, in _read_fmt_chunk raise Error, 'unknown format: %r' % (wFormatTag,) wave.Error: unknown format: 85 I read somewhere that there are various wave formats, only some supported by Python. Is this true? If so, is there any way I can convert my wave files into a supported kind? Thanks!

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getUncPath(mappedDrive)
by Albert-Jan Roskam Jan. 30, 2014

Jan. 30, 2014

Hi, Is there a function that takes a file path with a mapped drive (z:\blah) and returns the associated UNC path (\\server\share\ding\dang\dong\blah)? I looked in os.path, but it doesn't seem to have this. The link below seems to be a solution (code in the bottom of the page), but I can't install win32com.client in the office :-( Is there any built-in function? http://stackoverflow.com/questions/2244767/python-check-network-map Thanks! Regards, Albert-Jan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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keyboard interrupt
by Jim Mooney Oct. 17, 2013

Oct. 17, 2013

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 -- Jim Mooney

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How to unpack python-dateutil-2.0.tar.gz
by Richard D. Moores Sept. 5, 2013

Sept. 5, 2013

Python 3.2.3 64 bit MS Windows 7 Home Premium 64-bit SP1 I see python-dateutil recommended here from time to time, so I thought I'd try it out. I downloaded python-dateutil-2.1.tar.gz from http://pypi.python.org/pypi/python-dateutil but have forgotten how to unpack a .tar.gz file. Please remind me. Thanks, Dick Moores

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myown.getfilesystemencoding()
by Albert-Jan Roskam Sept. 4, 2013

Sept. 4, 2013

In Windows, sys.getfilesystemencoding() returns 'mbcs' (multibyte code system), which doesn't say very much imho. So I wrote the function below, which returns the codepage as reported by the windows chcp command. I noticed that the function returns 850 (codepage 850) when I run it via the command prompt, but 1252 (cp1252) when I run it in my IDE (Spyder). Any idea why? Is it a good idea anyway to make this function (no, probably, because Python devs are smart people ;-) #!python.exe #Python 2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 bit (Intel)] on win32 import subprocess, re, sys def getfilesystemencoding(): if sys.platform.startswith("win"): proc = subprocess.Popen("chcp", shell=True, stdout=subprocess.PIPE) m = re.search(": (?P<codepage>\d+)", proc.communicate()[0]) if m: return m.group("codepage") return sys.getfilesystemencoding() return sys.getfilesystemencoding() print getfilesystemencoding() Regards, Albert-Jan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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A mergesort
by D.V.N.Sarma డి.వి.ఎన్.శర్మ Sept. 3, 2013

Sept. 3, 2013

I have been searching for mergesort implimentations in python and came across this. def merge(a, b): if len(a)*len(b) == 0: return a+b v = (a[0] < b[0] and a or b).pop(0) return [v] + merge(a, b) def mergesort(lst): if len(lst) < 2: return lst m = len(lst)/2 return merge(mergesort(lst[:m]), mergesort(lst[m:])) mlst = [10, 9, 8, 4, 5, 6, 7, 3, 2, 1] sorted = mergesort(mlst) print sorted Besides using recursion in merge function also, it has somethings intresting. Especially the statement v = (a[0] < b[0] and a or b).pop(0) gives a.pop(0), if a[0] < b[0] otherwise b.pop(0). We have to look at the statement as v = ((a[0] < b[0] and a) or b).pop(0) regards, Sarma.

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how to save variables after a user quits in python
by Jack Little Aug. 31, 2013

Aug. 31, 2013

I am coding a game and I want the player to be able to quit the game and immediately take off right from where they started from. --Jack

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Best practice for generalizing and documenting each method's behaviour
by Bao Niu Aug. 30, 2013

Aug. 30, 2013

I'm starting a small project coding in Python as I learn the ropes. As the project grows bigger, there are more and more overlapping and even redundant methods. For example, several classes have a checkAndClean_obj_state() method. If just one or two such classes, it is easy to analyze the behaviour of them and design the optimal interaction for all objects. However, when there are many of such classes, exactly at what point to invoke check and clean behaviour becomes a little blurred. There is a desperate need for generalizing and documenting the behaviour of each such class, preferably in a flowchart. I'm currently doing the flowchart manually but the job becomes a bit overwhelming. I wonder what Python pros are using for analyzing and documenting classes/functions behaviours and interactions? Is UML the only way? Personally I found UML is a bit overkill for a one person project, but I'm not sure if it is the right direction. I'd appreciate any insight. Many thanks.

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Re: [Tutor] Comment on http://www.catb.org/esr/faqs/smart-questions.html
by Rick Moen Aug. 30, 2013

Aug. 30, 2013

/me waves to esteemed tutors and helpers. Quoting Bob Gailer (bgailer(a)gmail.com): > I have a reaction to > http://www.catb.org/esr/faqs/smart-questions.html and I'd like your > feedback. Perhaps I will then send revised comments to the authors of > the [essay]. As one of the essays' co-authors, I'm always interested in thoughts, especially ones about how to improve the fool thing. (As you'll see below , I have more than a few, myself.) > I found myself a bit disappointed. Me too. (No irony intended.) Eric and I never quite achieved what we hoped with it. > All I see at first is email links and Revision History. If I did not > know to scroll down I might have just figured I was at the wrong page. > > Reading translations and disclaimer is not why I'd come here. Personally, I'd have tried to put the links to translations and the revision history at the end, if possible. Eric maintains the master version, and IIRC uses a Docbook XML toolkit with a precooked stylesheet. I've never personally tried to significantly hack such tools to customise presentation. As maintainer of one Linuxdoc SGML-format FAQ and one Docbook SGML-format HOWTO for the Linux Documentation Project, I've long been a bit dissatisfied with the somewhat inflexible document structure the related toolkits push authors towards. Perhaps Eric found likewise; I'd have to ask him. Anyway, my point is that as an author, I'd generally rather spend time writing than hacking madly on document-production tools to rearrange the elements and alter the presentation. Time permitting, I do hope to get around to working with Eric to see if the order of elements can be rearranged with reasonable ease. However, there are much larger problems, which I'll get to in a minute. > With contact names and email at the bottom Objecting to e-mail links' living at the top doesn't seem reasonable, sorry. Those are merely the names of us co-authors. If it really bothers you to see authors' names at the top of what they write, Bob, you might want to quit the habit of reading before you become truly vexed, as you'll see it more often than not. Books in particular are going to be a huge disappointment to you. As to the 'disclaimer', can you guess _why_ it is there? Let me tell you, sir: For over a decade, every single day of every single year, I get at least a half dozen misdirected helpdesk requests in my personal e-mail. Most are for technical projects (mostly software, but not always) I've never even heard of. Often, they are demanding and downright rude in their insistance that I help the querent with $FOO for some bizarre value of FOO _right now_. I'm always nice to them and try to send them in the right direction, but _man_.... The 'disclaimer', the bit that says that Rick and Eric are not a helpdesk for several thousand projects they (mostly) haven't even heard of, and please for gosh sakes avoid pegging the irony metre and send your help requests to the right place, has cut the daily inflow. I used to get several dozen per day. I'm sorry you're annoyed by seeing it, but not moved to think it's a bad idea. Rather the contrary. If anything, I'm pondering the virtues of <blink> tags and red text, man.[1] > There's a lot of words to wade thru Exactly. That is the biggest problem, and it's fundamental such that it can be addressed properly only through a do-over. Let me recount what happened. Around 2000, Eric and I became aware that we were more-or-less writing the same sort of essay (except Eric's wording is pitched as advice to those seeking technical help from 'hackers', while I just was generically talking about online technical help). We joined forces, with Eric keeping the master copy and using his document-production toolchain. We put out a nice -little-, tightly focussed essay. To our astonishment, it proved very popular. Thousands (at minimum) of technical projects linked to it from their help pages. Correspondents kept asking us to add things: 'You should also cover $FOO.' We're obliging people and tried to accomodate most such requests. And they kept coming. Lather, rinse, repeat. Over ten years later, we now realise to our dismay: no more nice -little-, tightly focussed essay. What can I say? We tried, we wrote, people asked us to add more, we obliged, and the results have gradually become bloated. (Tolkien said 'It grew in the telling.' Ours did, too, albeit there the comparison ends.) Moreover, it's an unsatisfyingly linear piece, which is not really what is needed. _That_ along with sheer bloat makes it, IMO, fail at its original goal of helping frustrated and impatient people deal better with techincal projects' online help forums. So, I've been wanting to sit down and start over from scratch, and this time write a nice -little-, tightly focussed essay using a radically different format of some drill-down-for-more variety. Some toolkit hacking may be required -- or maybe just roll my own, in Python, starting from something like ReST rather than overengineered XML stuff. But I've not yet had time. Meanwhile, we're absolutely delighted when other people think they can do better, and enthusiastically encourage them to do so. I'm personally a big fan of Java Ranch's nice -little-, tightly focussed essay for people asking questions. > I also would not have come here to be potentially labeled an "idiot". Being a naive and cheerful optimist, I hope and expect you eventually noticed that Eric's and my essay neither stated nore implied that anyone is an idiot, Bob. We didn't even imply that idiots are idiots. Anyway, thank you for your thoughts. Quoting Emile van Sebille (emile(a)fenx.com): > In any case, I wouldn't write esr and Rick Moen to request changes -- > I expect you'd be pointed to > http://www.catb.org/esr/faqs/smart-questions.html#disclaimer if you got > a reply at all. We try to give thoughtful responses to anyone who writes us about the essay. After all, we share their desire for it to be useful to people (which is why we goodnaturedly kept adding more and more coverage to it upon request, although in retrospect we probably should have politely said no). Quoting Steven D'Aprano (steve(a)pearwood.info): > But really, I want to re-write them both [How to Ask Questiosn the > Smart Way and Short, Self-Contained, Correct Example] for a Python > audience. One day, when I get a round tuit. Please do. (Those circular tuits are scarce, I notice.) > In my feedback below, I'm going to attempt to channel ESR, As the saying goes, Eric's co-author is not chopped liver, by the way (but he is not taking offence). [1] If not ALL CAPS BOLD ITALIC RED TEXT WITH GREEN UNDERLINED SPACES BETWEEN WORDS. (Yes, I'm kidding.)

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