Search Results

Search found 15224 results on 609 pages for 'parallel python'.

Page 319/609 | < Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >

  • Parallelizing a serial algorithm

    - by user643813
    Hej folks, I am working on porting a Text mining/Natural language application from single-core to a Map-Reduce style system. One of the steps involves a while loop similar to this: Queue<Element>; while (!queue.empty()) { Element e = queue.next(); Set<Element> result = calculateResultSet(e); if (!result.empty()) { queue.addAll(result); } } Each iteration depends on the result of the one before (kind of). There is no way of determining the number of iterations this loop will have to perform. Is there a way of parallelizing a serial algorithm such as this one? I am trying to think of a feedback mechanism, that is able to provide its own input, but how would one go about parallelizing it? Thanks for any help/remarks

    Read the article

  • Making a video with opencv and ffmpeg. How to find the right color format?

    - by luc
    I have a webcam video recorder program built with python, opencv and ffmpeg It works ok except that the color of the video is more blue than the reality. The problem seems to come from color format of images. It seems that OpenCv is giving BGR images and ffmpeg+libx264 is expecting YUV420p. I've read that YUV420p correspond to YCbCr. opencv has no conversion from BGR to YCbCr. It only has a conversion to YCrCb. I have made some searchs and tried different alternatives to try converting opencv image to something that could be ok for ffmpeg+libx264. None is working. At this point, I am a bit lost and I would appreciate any pointer that could help me to fix this color issue.

    Read the article

  • app_label in an abstract Django model

    - by rayan
    Hi all, I'm trying to get an abstract model working in Django and I hit a brick wall trying to set the related_name per the recommendation here: http://docs.djangoproject.com/en/dev/topics/db/models/#be-careful-with-related-name This is what my abstract model looks like: class CommonModel(models.Model): created_on = models.DateTimeField(editable=False) creared_by = models.ForeignKey(User, related_name="%(app_label)s_%(class)s_created", editable=False) updated_on = models.DateTimeField(editable=False) updated_by = models.ForeignKey(User, related_name="%(app_label)s_%(class)s_updated", editable=False) def save(self): if not self.id: self.created_on = datetime.now() self.created_by = user.id self.updated_on = datetime.now() self.updated_by = user.id super(CommonModel, self).save() class Meta: abstract = True My common model is in [project_root]/models.py. It is the parent object of this model, which is located in an app called Feedback [project_root]/feedback/models.py: from django.db import models from mediasharks.models import CommonModel class Feedback(CommonModel): message = models.CharField(max_length=255) request_uri = models.CharField(max_length=255) domain = models.CharField(max_length=255) feedback_type = models.IntegerField() Basically I'm trying to set up a common model so that I'll always be able to tell when and by whom database entries were created. When I run "python manage.py validate" I get this error message: KeyError: 'app_label' Am I missing something here?

    Read the article

  • Error 500 on template.render() with jinja2

    - by Asperitas
    I am working on playing with some Python to create a webapp. At first I put the HTML in a string, using %s to fill certain elements. That all worked perfectly. Now I want to put the HTML in a template, so I followed this tutorial. My code looks like this (I deleted irrelevant code for this error): import codecs import cgi import os import jinja2 jinja_environment = jinja2.Environment(loader=jinja2.FileSystemLoader(os.path.join(os.path.dirname(__file__)))) class Rot13Handler(webapp2.RequestHandler): def get(self): template = jinja_environment.get_template('rot13.html') self.response.out.write(template.render({'text': ''})) When I replace just template.render({'text': ''}) a random string, the program works fine. I did add the latest jinja2 library to my app.yaml, and naturally my rot13.html does exist with the {{ text }} added. So could anyone please help me in the right direction? I don't know why it's going wrong.

    Read the article

  • add uchar values in ushort array with sse2 or sse3

    - by pompolus
    i have an unsigned short dst[16][16] matrix and a larger unsigned char src[m][n] matrix. Now i have to access in the src matrix and add a 16x16 submatrix to dst, using sse2 or ss3. In a my older implementation, I was sure that my summed values ??were never greater than 256, so i could do this: for (int row = 0; row < 16; ++row) { __m128i subMat = _mm_lddqu_si128(reinterpret_cast<const __m128i*>(src)); dst[row] = _mm_add_epi8(dst[row], subMat); src += W; // Step to next row i need to add } where W is an offset to reach the desired rows. This code works, but now my values in src are larger and summed could be greater than 256, so i need to store them as ushort. i've tried this: for (int row = 0; row < 16; ++row) { __m128i subMat = _mm_lddqu_si128(reinterpret_cast<const __m128i*>(src)); dst[row] = _mm_add_epi16(dst[row], subMat); src += W; // Step to next row i need to add } but it doesn't work. I'm not so good with sse, so any help will be appreciated.

    Read the article

  • Universal syntax file format?

    - by Isaiah
    Hey as a project to improve my programing skills I've begun programing a nice code editor in python to teach myself project management, version control, and gui programming. I was wanting to utilize syntax files made for other programs so I could have a large collection already. I was wondering if there was any kind of universal syntax file format much in the same sense as .odt files. I heard of one once in a forum, it had a website, but I can't remember it now. If not I may just try to use gedit syntax files or geany. thanks

    Read the article

  • How can i connect two or more machines via tcp cable to form a network grid?

    - by Gath
    How can i connect two or more machines to form a network grid and how can i distribute work load to the two machines? What operating systems do i need to run on the machines, and what application should i use to manage the load balancing? NB: I read somewhere that google uses cheap machines to perform this fete, how do they connect two network cards( 'Teaming' ) and distribute load across the machines? Good practical examples would serve me good, with actual code samples. Pointers to some good site i might read this stuff will be highly appreciated.

    Read the article

  • How to make pytest display a custom string representation for fixture parameters?

    - by Björn Pollex
    When using builtin types as fixture parameters, pytest prints out the value of the parameters in the test report. For example: @fixture(params=['hello', 'world'] def data(request): return request.param def test_something(data): pass Running this with py.test --verbose will print something like: test_example.py:7: test_something[hello] PASSED test_example.py:7: test_something[world] PASSED Note that the value of the parameter is printed in square brackets after the test name. Now, when using an object of a user-defined class as parameter, like so: class Param(object): def __init__(self, text): self.text = text @fixture(params=[Param('hello'), Param('world')] def data(request): return request.param def test_something(data): pass pytest will simply enumerate the number of values (p0, p1, etc.): test_example.py:7: test_something[p0] PASSED test_example.py:7: test_something[p1] PASSED This behavior does not change even when the user-defined class provides custom __str__ and __repr__ implementations. Is there any way to make pytest display something more useful than just p0 here? I am using pytest 2.5.2 on Python 2.7.6 on Windows 7.

    Read the article

  • Right design to validate attributes of a class instance

    - by systempuntoout
    Having a simple Python class like this: class Spam(object): __init__(self, description, value): self.description = description self.value = value Which is the correct approach to check these constraints: "description cannot be empty" "value must be greater than zero" Should i: 1.validate data before creating spam object ? 2.check data on __init__ method ? 3.create an is_valid method on Spam class and call it with spam.isValid() ? 4.create an is_valid static method on Spam class and call it with Spam.isValid(description, value) ? 5.check data on setters? 6.... Could you recommend a well designed\Pythonic\not verbose (on class with many attributes)\elegant approach?

    Read the article

  • Writing a script to bypass college login page

    - by gtredcvb
    My college has a silly login page that requires you to download a whole bunch of garbage that a lot of us don't need (Norton Anti-virus, Antispyware software, etc.). We have to have them running to get on the internet on campus. Though, if you are on Linux, or at least set your user-agent to linux, the requirements are gone. We could easily use Firefox with the useragent switcher to bypass this, but it'd be nice to create a script that automates this. How would this be possible? I figure this could be written in python, and could grab the webpage with curl specifying a user agent? How would I go about posting the data back to the servers? Thanks

    Read the article

  • Executing functions parallelly in PHP

    - by binaryLV
    Hi! Can PHP call a function and don't wait for it to return? So something like this: function callback($pause, $arg) { sleep($pause); echo $arg, "\n"; } header('Content-Type: text/plain'); fast_call_user_func_array('callback', array(3, 'three')); fast_call_user_func_array('callback', array(2, 'two')); fast_call_user_func_array('callback', array(1, 'one')); would output one (after 1 second) two (after 2 seconds) three (after 3 seconds) rather than three (after 3 seconds) two (after 3 + 2 = 5 seconds) one (after 3 + 2 + 1 = 6 seconds) Main script is intended to be run as a permanent process (TCP server). callback() function would receive data from client, execute external PHP script and then do something based on other arguments that are passed to callback(). The problem is that main script must not wait for external PHP script to finish. Result of external script is important, so exec('php -f file.php &') is not an option.

    Read the article

  • How do you handle options that can't be used together with OptionParser?

    - by Joel
    My Python script (for todo lists) is started from the command line like this: todo [options] <command> [command-options] Some options can not be used together, for example todo add --pos=3 --end "Ask Stackoverflow" would specify both the third position and the end of the list. Likewise todo list --brief --informative would confuse my program about being brief or informative. Since I want to have quite a powerful option control, cases like these will be a bunch, and new ones will surely arise in the future. If a users passes a bad combination of options, I want to give an informative message, preferably along with the usage help provided by optparse. Currently I handle this with an if-else statement that I find really ugly and poor. My dream is to have something like this in my code: parser.set_not_allowed(combination=["--pos", "--end"], message="--pos and --end can not be used together") and the OptionParser would use this when parsing the options. Since this doesn't exist as far as I know, I ask the SO community: How do you handle this?

    Read the article

  • QtWebkit and hasPendingEvents() always True

    - by Deorf
    Hello. I use project webkit2png (slightly appended) to take screenshots in Linux. On the server running the latest version QtWebkit and Python 2.6 On some sites (eg 118114.cn) problem and the application hangs forever. Debug shows that the problem in this code snippet: while self.__loading:    if timeout 0 and time.time() = cancelAt:       raise RuntimeError("Request timed out on %s" % url)    while QApplication.hasPendingEvents():       QCoreApplication.processEvents() Full version of the source code is available here (lines 270-275) Somehow Loading-event hangs and hasPendingEvents can not be False. Most of the screenshots are created normally, but sometimes due to some URL drops my app: ( Does anyone know how to solve this problem and why the event hangs?

    Read the article

  • Converting human readable date into integer values

    - by kahrn
    Hello all, I am looking to do something really simple. Merely convert a string, such as 'december' into something I can use with MySQL (such as '12'). At the moment I use a dict, month_map = { 'december': '12', 'november': '11', 'october': '10', 'september': '09', 'august': '08', 'july': '07', 'june': '06', 'may': '05', 'april': '04', 'march': '03', 'february': '02', 'january': '01' } and then month_map.get('december'). Does any function already exist within the standard python modules that can achieve this? Apologies if this has already been asked.. the questions I have found using search seem a little different.

    Read the article

  • reading csv file without for

    - by Abruzzo Forte e Gentile
    Hi All I need to read a CSV file in python. Since for last row I receive a 'NULL byte' error I would like to avoid using for keyword but the while. Do you know how to do that? reader = csv.reader( file ) for row in reader # I have an error at this line # do whatever with row I want to substitute the for-loop with a while-loop so that I can check if the row is NULL or not. What is the function for reading a single row in the CSV module? Thanks Thanks p.S. below the traceback Traceback (most recent call last): File "FetchNeuro_TodayTrades.py", line 189, in for row in reader: _csv.Error: line contains NULL byte

    Read the article

  • Access to an "upper" instance of a class from another instance of a different class

    - by BorrajaX
    Hello everyone! I have a tricky question and probably what I want to do is not even possible but... who knows... Python seems very flexible and powerful... I'd like to know if there's a way to access to the class (or its fields) where an object is instanciated. Let's say I have: def Class1: def __init__(self): self.title = "randomTitle" self.anotherField = float() self.class2Field = Class2() and the class whose type will be the class2Field: def Class2: def __init__(self): self.field1 = "" self.field2 = "" # . . . # I'd like to know if there's a way to access the instance of Class1 from the instance of Class2 that is declared in Class1 (meaning, accessing the fields of Class1 from the variable self.class2Field in that Class1 instance) I know I can always change the init in Class2 to accept a Class1 parameter, but I'd like to know if there's another way of "climbing" through the class hierachy... Thank you very much!

    Read the article

  • HTTP Download very Big File

    - by Luca
    I'm working at a web application in Python/Twisted. I want the user to be able to download a very big file ( 100 Mb). I don't want to load all the file in memory (of the server), of course. server side I have this idea: ... request.setHeader('Content-Type', 'text/plain') fp = open(fileName, 'rb') try: r = None while r != '': r = fp.read(1024) request.write(r) finally: fp.close() request.finish() I expected this to work, but I have problems: I'm testing with FF... It seems the browser make me wait until the file is completed downloaded, and then I have the open/save dialog box. I expected the dialog box immediately, and then the progress bar in action... Maybe I have to add something in the Http header... Something like the size of the file?

    Read the article

  • Why are C, C++, and LISP so prevalent in embedded devices and robots?

    - by David
    It seems that the software language skills most sought for embedded devices and robots are C, C++, and LISP. Why haven't more recent languages made inroads into these applications? For example, Erlang would seem particularly well-suited to robotic applications, since it makes concurrent programming easier and allows hot swapping of code. Python would seem to be useful, if for no other reason than its support of multiple programming paradigms. I'm even surprised that Java hasn't made a foray into general robotic programming. I'm sure one argument would be, "Some newer languages are interpreted, not compiled" - implying that compiled languages are quicker and use fewer computational resources. Is this still the case, in a time when we can put a Java Virtual Machine on a cell phone or a SunSpot? (and isn't LISP interpreted anyway?)

    Read the article

  • What is the pythonic way to add type information to an object's attributes?

    - by Tikitu
    I'm building classes where I know the types of the attributes, but Python of course doesn't. While it's un-pythonic to want to tell it, supposing I do want to, is there an idiomatic way to do so? Why: I'm reading in serialised data (without type information) involving objects-nested-inside-objects. It's easy to put it into nested dictionaries, but I want it in objects of my class-types, to get the right behaviours as well as the data. For instance: suppose my class Book has an attribute isbn which I will fill with an ISBNumber object. My serialised data gives me the isbn as a string; I would like to be able to look at Book and say "That field should be filled by ISBNumber(theString)." Bonus glee for me if the solution can be applied to classes I get from someone else without editing their code.

    Read the article

  • Merging contents of two lists based on a if-loop

    - by chavanak
    I have a minor problem while checking for elements in a list: I have two files with contents something like this file 1: file2: 47 358 47 48 450 49 49 56 50 I parsed both files into two lists and used the following code to check for i in file_1: for j in file_2: j = j.split() if i == j[1]: x=' '.join(j) I am now trying to get a "0" if the value of file_1 is not there in file_2 for example, value "48" is not there is file_2 so I need to get the output like (with only one space in between the two numbers): output_file: 358 47 0 48 450 49 56 50 I tried using the dictionary approach but I didn't quite get what I wanted (actually I don't know how to use dictionary in python correctly ;)). Any help will be great.

    Read the article

  • Unwanted behaviour from dict.fromkeys

    - by Anthony Labarre
    Hi there, I'd like to initialise a dictionary of sets (in Python 2.6) using dict.fromkeys, but the resulting structure behaves strangely. More specifically: >>>> x = {}.fromkeys(range(10), set([])) >>>> x {0: set([]), 1: set([]), 2: set([]), 3: set([]), 4: set([]), 5: set([]), 6: set([]), 7: set([]), 8: set([]), 9: set([])} >>>> x[5].add(3) >>>> x {0: set([3]), 1: set([3]), 2: set([3]), 3: set([3]), 4: set([3]), 5: set([3]), 6: set([3]), 7: set([3]), 8: set([3]), 9: set([3])} I obviously don't want to add 3 to all sets, only to the set that corresponds to x[5]. Of course, I can avoid the problem by initialising x without fromkeys, but I'd like to understand what I'm missing here.

    Read the article

  • Simple graphics API with transparency, polygons, reading image pixels?

    - by M. Elkstein
    I need a simple graphics library that supports the following functionality: Ability to draw polygons (not just rectangles!) with RGBA colors (i.e., partially transparent), Ability to load bitmap images, Ability to read current color of pixel in a given coordinate. Ideally using JavaScript or Python. Seems like HTML 5 Canvas can handle #2 and #3 but not #1, whereas SVG can handle #1 and #2 but not #3. Am I missing something (about either of these two)? Or are there other alternatives?

    Read the article

  • How to handle date difference between client and server?

    - by daydreamer
    I have an API which looks like /summary/yyyy/mm Which returns the summary of their data for the year and month requested. One of the things it returns the number of days left if this is current year and month. For example: days_left: 9 for 2013 and 10 and current date on server is 21 Oct 2013 How I calculate remaining days? This is implemented in python as def current_financial_month_details(self): time_from, time_to = self \ .get_start_end_time_current_financial_month() today = datetime.today() from_time = datetime(year=today.year, month=today.month, day=today.day) return { 'time_from': time_from, 'time_to': time_to, 'remaining_days': (time_to - from_time).days } The problem? The server is in east coast and the client(me with browser) is on pacific time zone When its 9PM PST the time changes in east coast, so if I run hit /summary/2013/10 and if it is Oct 21 2013 for me on PST, the date has already changed on EST, so days_left: 8 which is incorrect on client end. right? How do I handle this situation?

    Read the article

  • Opinions about Dabo

    - by driverate
    Has anyone used Dabo lately? How does it rate vs Boa Constructor, etc? I'm writing a new Python database app and Dabo looks promising, but what's the real-world scoop on it? Is it used by many developers? It's not talked about very much here on SO, or anywhere, as far as I can tell. I'm just a little concerned that the support community might be too small, or the possibility that writers might decide to throw in the towel. What is your assessment of Dabo?

    Read the article

< Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >