Search Results

Search found 13693 results on 548 pages for 'python metaprogramming'.

Page 152/548 | < Previous Page | 148 149 150 151 152 153 154 155 156 157 158 159  | Next Page >

  • how to build good python web application

    - by Moayyad Yaghi
    hello i never worked with web programming and i've been asked lately to write a web-based software to manage assets and tasks. to be used by more than 900 persons what are the recommended modules , frameworks , libraries for this task. and it will be highly appreciated if you guyz recommend some books and articles that might help me. thanks in advance

    Read the article

  • How to concat a string in Python

    - by alex
    query = "SELECT * FROM mytable WHERE time=%s", (mytime) Then, I want to add a limit %s to it. How can I do that without messing up the %s in mytime? Edit: I want to concat query2, which has "LIMIT %s, %s"

    Read the article

  • python iterators and thread-safety

    - by Igor
    I have a class which is being operated on by two functions. One function creates a list of widgets and writes it into the class: def updateWidgets(self): widgets = self.generateWidgetList() self.widgets = widgets the other function deals with the widgets in some way: def workOnWidgets(self): for widget in self.widgets: self.workOnWidget(widget) each of these functions runs in it's own thread. the question is, what happens if the updateWidgets() thread executes while the workOnWidgets() thread is running? I am assuming that the iterator created as part of the for...in loop will keep some kind of reference to the old self.widgets object? So I will finish iterating over the old list... but I'd love to know for sure.

    Read the article

  • Python beautiful soup arguments

    - by scott
    Hi I have this code that fetches some text from a page using BeautifulSoup soup= BeautifulSoup(html) body = soup.find('div' , {'id':'body'}) print body I would like to make this as a reusable function that takes in some htmltext and the tags to match it like the following def parse(html, atrs): soup= BeautifulSoup(html) body = soup.find(atrs) return body But if i make a call like this parse(htmlpage, ('div' , {'id':'body'}")) or like parse(htmlpage, ['div' , {'id':'body'}"]) I get only the div element, the body attribute seems to get ignored. Is there a way to fix this?

    Read the article

  • Small Python optional arguments question

    - by ooboo
    I have two functions: def f(a,b,c=g(b)): blabla def g(n): blabla c is an optional argument in function f. If the user does not specify its value, the program should compute g(b) and that would be the value of c. But the code does not compile - it says name 'b' is not defined. How to fix that? Someone suggested: def g(b): blabla def f(a,b,c=None): if c is None: c = g(b) blabla But this doesn't work, because maybe the user intended c to be None and then c will have another value.

    Read the article

  • Take the intersection of an arbitrary number of lists in python

    - by thepandaatemyface
    Suppose I have a list of lists of elements which are all the same (i'll use ints in this example) [range(100)[::4], range(100)[::3], range(100)[::2], range(100)[::1]] What would be a nice and/or efficient way to take the intersection of these lists (so you would get every element that is in each of the lists)? For the example that would be: [0, 12, 24, 36, 48, 60, 72, 84, 96]

    Read the article

  • Algorithm detect repeating/similiar strings in a corpus of data -- say email subjects, in Python

    - by RizwanK
    I'm downloading a long list of my email subject lines , with the intent of finding email lists that I was a member of years ago, and would want to purge them from my Gmail account (which is getting pretty slow.) I'm specifically thinking of newsletters that often come from the same address, and repeat the product/service/group's name in the subject. I'm aware that I could search/sort by the common occurrence of items from a particular email address (and I intend to), but I'd like to correlate that data with repeating subject lines.... Now, many subject lines would fail a string match, but "Google Friends : Our latest news" "Google Friends : What we're doing today" are more similar to each other than a random subject line, as is: "Virgin Airlines has a great sale today" "Take a flight with Virgin Airlines" So -- how can I start to automagically extract trends/examples of strings that may be more similar. Approaches I've considered and discarded ('because there must be some better way'): Extracting all the possible substrings and ordering them by how often they show up, and manually selecting relevant ones Stripping off the first word or two and then count the occurrence of each sub string Comparing Levenshtein distance between entries Some sort of string similarity index ... Most of these were rejected for massive inefficiency or likelyhood of a vast amount of manual intervention required. I guess I need some sort of fuzzy string matching..? In the end, I can think of kludgy ways of doing this, but I'm looking for something more generic so I've added to my set of tools rather than special casing for this data set. After this, I'd be matching the occurring of particular subject strings with 'From' addresses - I'm not sure if there's a good way of building a data structure that represents how likely/not two messages are part of the 'same email list' or by filtering all my email subjects/from addresses into pools of likely 'related' emails and not -- but that's a problem to solve after this one. Any guidance would be appreciated.

    Read the article

  • Working with multiple input and output files in Python

    - by Morlock
    I need to open multiple files (2 input and 2 output files), do complex manipulations on the lines from input files and then append results at the end of 2 output files. I am currently using the following approach: in_1 = open(input_1) in_2 = open(input_2) out_1 = open(output_1, "w") out_2 = open(output_2, "w") # Read one line from each 'in_' file # Do many operations on the DNA sequences included in the input files # Append one line to each 'out_' file in_1.close() in_2.close() out_1.close() out_2.close() The files are huge (each potentially approaching 1Go, that is why I am reading through these input files one at a time. I am guessing that this is not a very Pythonic way to do things. :) Would using the following form good? with open("file1") as f1: with open("file2") as f2: # etc. If yes, could I do it while avoiding the highly indented code that would result? Thanks for the insights!

    Read the article

  • Get Path of Uploaded File using Python

    - by Ali
    Is it possible to get the full path of the file on the user's computer being uploaded to my site? Using os.path.abspath(fileitem.filename) simply gets me the address of where my script is executing from on my shared hosting server. FYI: fileitem = form['file'] and form = cgi.FieldStorage()

    Read the article

  • How to remove commas etc form a matrix in python

    - by robert
    say ive got a matrix that looks like: [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]] how can i make it on seperate lines: [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]] and then remove commas etc: 0 0 0 0 0 And also to make it blank instead of 0's, so that numbers can be put in later, so in the end it will be like: _ 1 2 _ 1 _ 1 (spaces not underscores) thanks

    Read the article

  • Dynamic dispatch and inheritance in python

    - by Bill Zimmerman
    Hi, I'm trying to modify Guido's multimethod (dynamic dispatch code): http://www.artima.com/weblogs/viewpost.jsp?thread=101605 to handle inheritance and possibly out of order arguments. e.g. (inheritance problem) class A(object): pass class B(A): pass @multimethod(A,A) def foo(arg1,arg2): print 'works' foo(A(),A()) #works foo(A(),B()) #fails Is there a better way than iteratively checking for the super() of each item until one is found? e.g. (argument ordering problem) I was thinking of this from a collision detection standpoint. e.g. foo(Car(),Truck()) and foo(Truck(), Car()) and should both trigger foo(Car,Truck) # Note: @multimethod(Truck,Car) will throw an exception if @multimethod(Car,Truck) was registered first? I'm looking specifically for an 'elegant' solution. I know that I could just brute force my way through all the possibilities, but I'm trying to avoid that. I just wanted to get some input/ideas before sitting down and pounding out a solution. Thanks

    Read the article

  • Writing white space to CSV fields in Python?

    - by matt
    When I try to write a field that includes whitespace in it, it gets split into multiple fields on the space. What's causing this? It's driving me insane. Thanks data = open("file.csv", "wb") w = csv.writer(data) w.writerow(['word1', 'word2']) w.writerow(['word 1', 'word2']) data.close() I'll get 2 fields(word1,word2) for first example and 3(word,1,word2) for the second.

    Read the article

  • python threading and performace?

    - by kumar
    I had to do heavy I/o bound operation, i.e Parsing large files and converting from one format to other format. Initially I used to do it serially, i.e parsing one after another..! Performance was very poor ( it used take 90+ seconds). So I decided to use threading to improve the performance. I created one thread for each file. ( 4 threads) for file in file_list: t=threading.Thread(target = self.convertfile,args = file) t.start() ts.append(t) for t in ts: t.join() But for my astonishment, there is no performance improvement whatsoever. Now also it takes around 90+ seconds to complete the task. As this is I/o bound operation , I had expected to improve the performance. What am I doing wrong?

    Read the article

  • Google App Engine python - Self is not defined

    - by sdasdas
    I have a request that maps to this class ChatMsg It takes in 3 get variables, username, roomname, and msg. But it fails on this last line here. class ChatMsg(webapp.RequestHandler): # this is line 239 def get(self): username = urllib.unquote(self.request.get('username')) roomname = urllib.unquote(self.request.get('roomname')) # this is line 242 When it tries to assign roomname, it tells me: <type 'exceptions.NameError'>: name 'self' is not defined Traceback (most recent call last): File "/base/data/home/apps/chatboxes/1.341998073649951735/chatroom.py", line 239, in <module> class ChatMsg(webapp.RequestHandler): File "/base/data/home/apps/chatboxes/1.341998073649951735/chatroom.py", line 242, in ChatMsg roomname = urllib.unquote(self.request.get('roomname')) what the hell is going on to make self not defined

    Read the article

  • Python datetime to Unix timestamp

    - by Off Rhoden
    I have to create an "Expires" value 5 minutes in the future, but I have to supply it in UNIX Timestamp format. I have this so far, but it seems like a hack. def expires(): '''return a UNIX style timestamp representing 5 minutes from now''' epoch = datetime.datetime(1970, 1, 1) seconds_in_a_day = 60 * 60 * 24 five_minutes = datetime.timedelta(seconds=5*60) five_minutes_from_now = datetime.datetime.now() + five_minutes since_epoch = five_minutes_from_now - epoch return since_epoch.days * seconds_in_a_day + since_epoch.seconds Is there a module or function that does the timestamp conversion for me?

    Read the article

  • Parsing text file in python

    - by Ockonal
    Hello, I have html-file. I have to replace all text between this: [%anytext%]. As I understand, it's very easy to do with BeautifulSoup for parsing hmtl. But what is regular expression and how to remove&write back text data?

    Read the article

  • How do I calculate percentiles with python/numpy?

    - by Uri
    Is there a convenient way to calculate percentiles for a sequence or single-dimensional numpy array? I am looking for something similar to Excel's percentile function. I looked in NumPy's statistics reference, and couldn't find this. All I could find is the median (50th percentile), but not something more specific.

    Read the article

  • Redirect print in Python: val = print(arg) to output mixed iterable to file

    - by emcee
    So lets say I have an incredibly nested iterable of lists/dictionaries. I would like to print them to a file as easily as possible. Why can't I just redirect print to a file? val = print(arg) gets a SyntaxError. Is there a way to access stdinput? And why does print take forever with massive strings? Bad programming on my side for outputting massive strings, but quick debugging--and isn't that leveraging the strength of an interactive prompt? There's probably also an easier way than my gripe. Has the hive-mind an answer?

    Read the article

  • Python - Things one MUST avoid

    - by Anurag Uniyal
    Today I was bitten again by "Mutable default arguments" after many years. I usually don't use mutable default arguments unless needed but I think with time I forgot about that, and today in the application I added tocElements=[] in a pdf generation function's argument list and now 'Table of Content' gets longer and longer after each invocation of "generate pdf" :) My question is what other things should I add to my list of things to MUST avoid? 1 Mutable default arguments 2 import modules always same way e.g. 'from y import x' and 'import x' are totally different things actually they are treated as different modules see http://stackoverflow.com/questions/1459236/module-reimported-if-imported-from-different-path 3 Do not use range in place of lists because range() will become an iterator anyway, so things like this will fail, so wrap it by list myIndexList = [0,1,3] isListSorted = myIndexList == range(3) # will fail in 3.0 isListSorted = myIndexList == list(range(3)) # will not same thing can be mistakenly done with xrange e.g myIndexList == xrange(3). 4 Catching multiple exceptions try: raise KeyError("hmm bug") except KeyError,TypeError: print TypeError It prints "hmm bug", though it is not a bug, it looks like we are catching exceptions of type KeyError,TypeError but instead we are catching KeyError only as variable TypeError, instead use try: raise KeyError("hmm bug") except (KeyError,TypeError): print TypeError

    Read the article

  • Python modify an xml file

    - by michele
    I have this xml model. link text So I have to add some node (see the text commented) to this file. How I can do it? I have writed this partial code but it doesn't work: xmldoc=minidom.parse(directory) child = xmldoc.createElement("map") for node in xmldoc.getElementsByTagName("Environment"): node.appendChild(child) Thanks in advance.

    Read the article

< Previous Page | 148 149 150 151 152 153 154 155 156 157 158 159  | Next Page >