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  • Python vs. Perl in ten years time

    - by Richard
    If you were starting learning a new language today, for scripting and doing "various stuff" with it (from making useful programs to it being glue to several command line programs), would you go with Python or Perl (or some third option, although the battle usually comes to these two)? I've never much used dynamic languages at all, having been able to do everything I needed in traditional static ones. Did some scripting in Perl a couple of years ago, but that was more of a momentary fling, than an attempt to learn it well. Now I've some free time, and have decided to go along with one of these two, and play a little with them. I like Perl's syntax, but Python does seem to be taking rather big steps on overtaking that area. What do you think, which one is more worth learning and why? Also, what do you think, what will be Python's future in about 10 years ... will it overtake Perl and other scripting languages's as a dominant tool for that kind of work (I more often than not find it being implemented in various applications I'm using - for internal scripting and automating loading of data and similar operations), or will it find a balance and coexist along others (Perl)? What is its current "momentum" - does it comes by default with Linux distributions, as Perl does, or does it needs to be installed separately every time? Is it a language which can be expected "to just be there"?

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  • UBJsonReader (Libgdx) unable to to read UBJson from Python(Blender)

    - by daniel
    I am working on an export tool from Blender to Libgdx, exports like custom attributes and other information (Almost completed), this is a very cool tool that will speed up a lot your works, after I completed I will send to public to contribute forum, Export format is uses python's Standard Json module and readable text, it of course works fine, but I wanna also have a Binary Json export for faster load, so users can Export Straight to Libgdx, but after I search I found that UBJson with draft9.py (simpleubjson 0.6.1) encode is seems matches with one FBXConverter's UBJsonWriter( Xoppa wrote), but when I export, I am not able to read the file, and send this errors (Java heap space) seems this is a different between byte sizes in UBJson(python) and UBJsonReader. how can I write a correct one in python that matches with Libgdx's UBJsonReader, and would be cross-platform? Exception in thread "LWJGL Application" com.badlogic.gdx.utils.GdxRuntimeException: java.lang.OutOfMemoryError: Java heap space at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:120) Caused by: java.lang.OutOfMemoryError: Java heap space at com.badlogic.gdx.utils.UBJsonReader.readString(UBJsonReader.java:162) at com.badlogic.gdx.utils.UBJsonReader.parseString(UBJsonReader.java:150) at com.badlogic.gdx.utils.UBJsonReader.parseObject(UBJsonReader.java:112) at com.badlogic.gdx.utils.UBJsonReader.parse(UBJsonReader.java:59) at com.badlogic.gdx.utils.UBJsonReader.parse(UBJsonReader.java:52) at com.badlogic.gdx.utils.UBJsonReader.parse(UBJsonReader.java:36) at com.badlogic.gdx.utils.UBJsonReader.parse(UBJsonReader.java:45) at com.me.gdximportexport.GdxImportExport.create(GdxImportExport.java:43) at com.badlogic.gdx.backends.lwjgl.LwjglApplication.mainLoop(LwjglApplication.java:136) at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:114) Tested on UbuntuStudio 13.10 with OpenJdk 7, and Windows 7 with jdk 7 Thanks for any guides.

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  • Browser-based GUI for a python application

    - by ack__
    I want to create a web/browser-based GUI for a command-line python application. The goal is to make use of HTML/JS technologies to create this GUI. As the application itself, it needs to run on Linux and Windows, and the interface will be accessible only from localhost (not exposed to internet). The GUI will contain 5 to 10 pages. I don't want a traditional desktop GUI that includes HTML/JS, but just a bunch of html files and some kind of controller between those and the application. I also want to make use of asynchronous programming (ajax like) so I can load and print data in the GUI without refreshing the whole page. I'd probably use jQuery for that and a couple other things. How would you recommend to design this? Performance is not the key here, I'm rather looking at reliability, portability and simplicity. I'm thinking of using a lightweight python HTTP server / framework (like CherryPy) and maybe later a Python templating system (at the begining it will just be a couple pages). EDIT: I'm looking for ideas/recommendations how to build this, not for alternatives to browser/web-based GUI.

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  • Python web frameworks comparisons

    - by stupidLearner
    I recently asked a question on SO about Python web frameworks: http://stackoverflow.com/questions/4909306/python-web-frameworks-vs-java-web-frameworks-how-is-web-development-in-python-do I want to learn one just for fun but it also has to be able to help me deliver a proper working application. I am looking for a framework with lots of features, powerful, mature, with large community, good documentation, books etc. I need something that will help me be more productive in developing my app and not waste time figuring out how to do a certain thing in the framework or how to write workaround around the limitations of the framework. I was thinking one of the following: django, zope, turbogears, pylons. Off course the war is raging out there and there are other alternatives but seems Django is at the top... or is it just hype? I am interested in pros and cons of each. What was the best feature you think the framework has? What is the thing it lacks? What could have been done differently. Help me chose one to learn for starters.

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  • Duck checker in Python: does one exist?

    - by elliot42
    Python uses duck-typing, rather than static type checking. But many of the same concerns ultimately apply: does an object have the desired methods and attributes? Do those attributes have valid, in-range values? Whether you're writing constraints in code, or writing test cases, or validating user input, or just debugging, inevitably somewhere you'll need to verify that an object is still in a proper state--that it still "looks like a duck" and "quacks like a duck." In statically typed languages you can simply declare "int x", and anytime you create or mutate x, it will always be a valid int. It seems feasible to decorate a Python object to ensure that it is valid under certain constraints, and that every time that object is mutated it is still valid under those constraints. Ideally there would be a simple declarative syntax to express "hasattr length and length is non-negative" (not in those words. Not unlike Rails validators, but less human-language and more programming-language). You could think of this as ad-hoc interface/type system, or you could think of it as an ever-present object-level unit test. Does such a library exist to declare and validate constraint/duck-checking on Python-objects? Is this an unreasonable tool to want? :) (Thanks!) Contrived example: rectangle = {'length': 5, 'width': 10} # We live in a fictional universe where multiplication is super expensive. # Therefore any time we multiply, we need to cache the results. def area(rect): if 'area' in rect: return rect['area'] rect['area'] = rect['length'] * rect['width'] return rect['area'] print area(rectangle) rectangle['length'] = 15 print area(rectangle) # compare expected vs. actual output! # imagine the same thing with object attributes rather than dictionary keys.

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  • Is C and Python enough?

    - by gruszczy
    I am very proficient in Python (including Django), which I use for most tasks. I am also quite confident with C; I am maintaining small file system in userspace written in C. Yet when I am browsing job offers I see everywhere Java/C# and sometimes C++. I have coded profesionally in C++ for half a year in a gaming company, but I don't consider myself a pro. Also I simply despise Java and C#, which I would prefer not to touch ever. But it seems to me, that I am at very unfavorable position, when it comes to career. I am browsing careers.stackoverflow.com and I don't see and pure python or C offers. I would like to find a new job abroad in about 6 months. If I find some python offer, it means doing web development (not my favorite job). Does it mean, that I have to quickly start improving my C++ skills, if I wish to find a satisfying job? What would you suggest me? EDIT Learning new technologies is not an issue. Company I am working in is an integrator. Basically every new project requires learning new technologies, sometimes custom made. During last two years I was writing SQLs by hand, using LDAP, writing GUI in Qt, working on large scale DBMS prototype, making our internal help desk system use gsm modem or writing own report system. In previous job I had to learn from basics everything what I could about games development, because I knew nothing and chose this job only because of the challene it posed. I am all about embracing new technologies. I have used Java in the past and simply didn't like it. It's dull and boring. Doesn't let me do anything cool. I have recently seen some C# in action and seems similar. I don't like it. It's like German. I don't like speaking German.

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  • Experience of Python's “PEP-302 New Import Hooks”

    - by Koichi Sasada
    I'm one of the developers of Ruby (CRuby). We are working on Ruby 2.0 release (planned to release 2012/Feb). Python has "PEP302: New Import Hooks" (2003): This PEP proposes to add a new set of import hooks that offer better customization of the Python import mechanism. Contrary to the current import hook, a new-style hook can be injected into the existing scheme, allowing for a finer grained control of how modules are found and how they are loaded. We are considering introducing a feature similar to PEP302 into Ruby 2.0 (CRuby 2.0). I want to make a proposal which can persuade Matz. Currently, CRuby can load scripts from only file systems in a standard way. If you have any experience or consideration about PEP 302, please share. Example: It's a great spec. No need to change it. It is almost good, but it has this problem... If I could go back to 2003, then I would change the spec to... I'm sorry if such a question is not suitable for here. I posted here because I'm not sure that I can ask this question at python-dev (of course, the list is not for cruby development). This post is moved from http://stackoverflow.com/questions/11188229/experience-of-pythons-pep-302-new-import-hooks.

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  • still about perl vs python but (to me) slightly different from what has been asked [closed]

    - by B Chen
    Being a newbie to coding, I read from this site that Perl is still as viable as it has been, while Python, quoted from someone else's post, is good but just "snake oil" (not sure what this refers to exactly though). So from the responses in that post, I got the gist that Perl is good and worthy to learn. My question is - pardon me for phrasing it in this "non-programmer's" way - Which one should I learn FIRST? (I am actually currently learning R) Here below is the background info - (a) I will be using it mostly for data mining and statistics analysis (b) Will there be this "first" and "later" issue with learning either Perl or Python? That is, after I become competent with one language, would there be a need to learn the second one (for a similar task??) (c) If there should be circumstances where I must learn the second one, would learning Perl FIRST be better than learning Python? I hope to learn as much from exchanging info here, so please help provide with more than just "it depends" type of info. Great many thanks to all who choose to respond to my query.

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  • python pdb not breaking in files properly?

    - by YGA
    Hi Folks, I wish I could provide a simple sample case that occurs using standard library code, but unfortunately it only happens when using one of our in-house libraries that in turn is built on top of sql alchemy. Basically, the problem is that this break command: (Pdb) print sqlalchemy.engine.base.__file__ /prod/eggs/SQLAlchemy-0.5.5-py2.5.egg/sqlalchemy/engine/base.py (Pdb) break /prod/eggs/SQLAlchemy-0.5.5-py2.5.egg/sqlalchemy/engine/base.py:946 Is just being totally ignored, it seems, by pdb. As in, even though I am positive the code is being hit (both because I can see log messages, and because I've used sys.settrace to check which lines in which files are being hit), pdb is just not breaking there. I suspect that somehow the use of an egg is confusing pdb as to what files are being used (I can't reproduce the error if I use a non-egg'ed library, like pickle; there everything works fine). It's a shot in the dark, but has anyone come across this before? Thanks, /YGA

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  • How to implement ctypes in IronPython

    - by Walter
    I need help. I have a code which is passing a script into a DLL and initialize the instrument. But, one of the code unable to use in IronPython beside python 2.7 and 3.3 I have attached the code as below enter code here import ctypes import time, sys DLLHANDLE=ctypes.cdll.LoadLibrary("C:\\INSTRDLL\\builds\\DCSOURCEDLL\\B2902A.dll") INPUTSCRIPT="SYSTEM{DCSOURCE1|INIT}" INPUTVOLTAGE=0.0 c_INPUTSCRIPT=ctypes.c_char_p(INPUTSCRIPT) c_INPUTVOLTAGE=ctypes.c_double(INPUTVOLTAGE) SOURCEHANDLE=DLLHANDLE.DCSOURCE(c_INPUTSCRIPT,c_INPUTVOLTAGE) time.sleep(1) Once "SOURCEHANDLE=DLLHANDLE.DCSOURCE(c_INPUTSCRIPT,c_INPUTVOLTAGE)" is triggered, Ironpython will crash automatically and no idea how to resolve it... or any workaround solution? Please advice..

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  • SSRS: Report loading external images, image not found, can I hide the image control

    - by Nauman
    My SSRS report loads logo images for each customer from a customer number specific folder on the report server. I write an expression, to form my URL to the image based on th customer number. ..."http://localhost/images/" + iCustomerNumber.ToString() + "/logo.gif" I am able to get this working, but the problem I face is, when a particular customer doesn't has an image, then my report shows a red X mark in place of the logo. In this case, I expect to hide the image control itself. Any thoughts???? The other dirty solution will be to ensure that each customer specific folder has the designated image! even if there is no logo for a customer, I'll place a blank.gif or a spacer.gif of probably a square pixel in dimension!.

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  • ASP.NET store Image in SQL and retrieve for Asp:Image

    - by sweetcoder
    I am looking to fileupload a picture jpeg,gif,etc into an SQL database on an updateprofilepicture page. Then on the profile page, I want to retrieve the image from an sql database and have it show up in an Asp:Image control. I have much code trying to do this and it doesn't work. The table contains a column of type Image.

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  • Image drawing library for Haskell?

    - by absz
    I'm working on a Haskell program for playing spatial games: I have a graph of a bunch of "individuals" playing the Prisoner's Dilemma, but only with their immediate neighbors, and copying the strategies of the people who do best. I've reached a point where I need to draw an image of the world, and this is where I've hit problems. Two of the possible geometries are easy: if people have four or eight neighbors each, then I represent each one as a filled square (with color corresponding to strategy) and tile the plane with these. However, I also have a situation where people have six neighbors (hexagons) or three neighbors (triangles). My question, then, is: what's a good Haskell library for creating images and drawing shapes on them? I'd prefer that it create PNGs, but I'm not incredibly picky. I was originally using Graphics.GD, but it only exports bindings to functions for drawing points, lines, arcs, ellipses, and non-rotated rectangles, which is not sufficient for my purposes (unless I want to draw hexagons pixel by pixel*). I looked into using foreign import, but it's proving a bit of a hassle (partly because the polygon-drawing function requires an array of gdPoint structs), and given that my requirements may grow, it would be nice to use an in-Haskell solution and not have to muck about with the FFI (though if push comes to shove, I'm willing to do that). Any suggestions? * That is also an option, actually; any tips on how to do that would also be appreciated, though I think a library would be easier.

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  • Image Data via Ajax - how can I display the image on the Page

    - by Mike B
    I am creating a Domino Document via AJAX that contains a photo. I am able to get the base64 image data back to the server in a Notes Domino Document. Data is stored in a Richtext (textarea) field as "data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAFA..........." - (this goes on for several lines) I am trying to display on the Domino Webpage using passthru tag <<image id= "pic1" >> in the onLoad event of the Form i try to shove the data into the image element using this code: //Photo Stuff alert(document.forms[0].photo1.value); document.getElementById("pic1").src = document.forms[0].photo1.value; The alert is showing the data. Picture is not appearing. Please help. Thanks Mike

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  • turning text into image - PHP/GD - save image

    - by Phil Jackson
    Hi, I'm using this script to simply create an image from text. What I would like to know is how to save the image instead of printing straight to browser; // an email address in a string $string = $post[$key]; // some variables to set $font = 4; $width = ImageFontWidth($font) * strlen($string); $height = ImageFontHeight($font); // lets begin by creating an image $im = @imagecreatetruecolor ($width,$height); //white background $background_color = imagecolorallocate ($im, 255, 255, 255); //black text $text_color = imagecolorallocate ($im, 0, 0, 0); // put it all together $image = imagestring ($im, $font, 0, 0, $string, $text_color); I know its probably just one line of code at the end but im not sure which GD function to use. Any help would be much appreciated, Regards, Phil.

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  • Dynamically reducing image dimension as well as image size in C#

    - by hanesjw
    I have an image gallery that is created using a repeater control. The repeater gets bound inside my code behind file to a table that contains various image paths. The images in my repeater are populated like this <img src='<%# Eval("PicturePath")' %>' height='200px' width='150px'/> (or something along those lines, I don't recall the exact syntax) The problem is sometimes the images themselves are massive so the load times are a little ridiculous. And populating a 150x200px image definitely should not require a 3MB file. Is there a way I can not only change the image dimensions, but shrink the file size down as well? Thanks!

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  • Why did Apple remove Python support in Mavericks, aka Mac OS X 10.9?

    - by alex gray
    Apple has removed Python support (at least on the Developer level) in 10.9. Python IS still on the machine in /System/Library/Frameworks/Python.framework... but trying to link to Python using the 10.9 SDK fails. /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/System/Library/Frameworks does not have Python. I'm not a Pythonista, but find it interesting that Apple has made this change. I don't understand why this is done and I'm a bit annoyed that I have to remove Python from my compilation units in order to compile with 10.9 SDK. Is this a statement by Apple, along the lines of "People aren't using Python very much anymore so we're going to phase out support"? Or was something else driving the change?

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  • Compound assignment operators in Python's Numpy library

    - by Leonard
    The "vectorizing" of fancy indexing by Python's numpy library sometimes gives unexpected results. For example: import numpy a = numpy.zeros((1000,4), dtype='uint32') b = numpy.zeros((1000,4), dtype='uint32') i = numpy.random.random_integers(0,999,1000) j = numpy.random.random_integers(0,3,1000) a[i,j] += 1 for k in xrange(1000): b[i[k],j[k]] += 1 Gives different results in the arrays 'a' and 'b' (i.e. the appearance of tuple (i,j) appears as 1 in 'a' regardless of repeats, whereas repeats are counted in 'b'). This is easily verified as follows: numpy.sum(a) 883 numpy.sum(b) 1000 It is also notable that the fancy indexing version is almost two orders of magnitude faster than the for loop. My question is: "Is there an efficient way for numpy to compute the repeat counts as implemented using the for loop in the provided example?"

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  • How To Get Web Site Thumbnail Image In ASP.NET

    - by SAMIR BHOGAYTA
    Overview One very common requirement of many web applications is to display a thumbnail image of a web site. A typical example is to provide a link to a dynamic website displaying its current thumbnail image, or displaying images of websites with their links as a result of search (I love to see it on Google). Microsoft .NET Framework 2.0 makes it quite easier to do it in a ASP.NET application. Background In order to generate image of a web page, first we need to load the web page to get their html code, and then this html needs to be rendered in a web browser. After that, a screen shot can be taken easily. I think there is no easier way to do this. Before .NET framework 2.0 it was quite difficult to use a web browser in C# or VB.NET because we either have to use COM+ interoperability or third party controls which becomes headache later. WebBrowser control in .NET framework 2.0 In .NET framework 2.0 we have a new Windows Forms WebBrowser control which is a wrapper around old shwdoc.dll. All you really need to do is to drop a WebBrowser control from your Toolbox on your form in .NET framework 2.0. If you have not used WebBrowser control yet, it's quite easy to use and very consistent with other Windows Forms controls. Some important methods of WebBrowser control are. public bool GoBack(); public bool GoForward(); public void GoHome(); public void GoSearch(); public void Navigate(Uri url); public void DrawToBitmap(Bitmap bitmap, Rectangle targetBounds); These methods are self explanatory with their names like Navigate function which redirects browser to provided URL. It also has a number of useful overloads. The DrawToBitmap (inherited from Control) draws the current image of WebBrowser to the provided bitmap. Using WebBrowser control in ASP.NET 2.0 The Solution Let's start to implement the solution which we discussed above. First we will define a static method to get the web site thumbnail image. public static Bitmap GetWebSiteThumbnail(string Url, int BrowserWidth, int BrowserHeight, int ThumbnailWidth, int ThumbnailHeight) { WebsiteThumbnailImage thumbnailGenerator = new WebsiteThumbnailImage(Url, BrowserWidth, BrowserHeight, ThumbnailWidth, ThumbnailHeight); return thumbnailGenerator.GenerateWebSiteThumbnailImage(); } The WebsiteThumbnailImage class will have a public method named GenerateWebSiteThumbnailImage which will generate the website thumbnail image in a separate STA thread and wait for the thread to exit. In this case, I decided to Join method of Thread class to block the initial calling thread until the bitmap is actually available, and then return the generated web site thumbnail. public Bitmap GenerateWebSiteThumbnailImage() { Thread m_thread = new Thread(new ThreadStart(_GenerateWebSiteThumbnailImage)); m_thread.SetApartmentState(ApartmentState.STA); m_thread.Start(); m_thread.Join(); return m_Bitmap; } The _GenerateWebSiteThumbnailImage will create a WebBrowser control object and navigate to the provided Url. We also register for the DocumentCompleted event of the web browser control to take screen shot of the web page. To pass the flow to the other controls we need to perform a method call to Application.DoEvents(); and wait for the completion of the navigation until the browser state changes to Complete in a loop. private void _GenerateWebSiteThumbnailImage() { WebBrowser m_WebBrowser = new WebBrowser(); m_WebBrowser.ScrollBarsEnabled = false; m_WebBrowser.Navigate(m_Url); m_WebBrowser.DocumentCompleted += new WebBrowserDocument CompletedEventHandler(WebBrowser_DocumentCompleted); while (m_WebBrowser.ReadyState != WebBrowserReadyState.Complete) Application.DoEvents(); m_WebBrowser.Dispose(); } The DocumentCompleted event will be fired when the navigation is completed and the browser is ready for screen shot. We will get screen shot using DrawToBitmap method as described previously which will return the bitmap of the web browser. Then the thumbnail image is generated using GetThumbnailImage method of Bitmap class passing it the required thumbnail image width and height. private void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e) { WebBrowser m_WebBrowser = (WebBrowser)sender; m_WebBrowser.ClientSize = new Size(this.m_BrowserWidth, this.m_BrowserHeight); m_WebBrowser.ScrollBarsEnabled = false; m_Bitmap = new Bitmap(m_WebBrowser.Bounds.Width, m_WebBrowser.Bounds.Height); m_WebBrowser.BringToFront(); m_WebBrowser.DrawToBitmap(m_Bitmap, m_WebBrowser.Bounds); m_Bitmap = (Bitmap)m_Bitmap.GetThumbnailImage(m_ThumbnailWidth, m_ThumbnailHeight, null, IntPtr.Zero); } One more example here : http://www.codeproject.com/KB/aspnet/Website_URL_Screenshot.aspx

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  • Why should we use low level languages if a high level one like python can do almost everything? [closed]

    - by killown
    I know python is not suitable for things like microcontrolers, make drivers etc, but besides that, you can do everything using python, companys get stuck with speed optimizations for real hard time system but does forget other factors which one you can just upgrade your hardware for speed proposes in order to get your python program fit in it, if you think how much cust can the company have to maintain a system written in C, the comparison is like that: for example: 10 programmers to mantain a system written in c and just one programmer to mantain a system written in python, with python you can buy some better hardware to fit your python program, I think that low level languages tend to get more cost, since programmers aren't so cheaply than a hardware upgrade, then, this is my point, why should a system be written in c instead of python?

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  • Good library for search text tokenization

    - by Chris Dutrow
    Looking to tokenize some text in the same or similar way in which a search engine would do it. The reason we are doing this is so that we can run some statistical analysis on the tokens. The language we are using is python, so would prefer a library in that language, but could probably set something up to use another language if necessary. Example Original token: We have some great burritos! More simplified: (remove plurals and punctuation) We have some great burrito Even more simplified: (remove superfluous words) great burrito Best: (recognize positive and negative meaning): burrito -positive-

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  • Inserting an Image into a PDF

    - by Cerin
    Are there Linux/Ubuntu programs capable of inserting a partially transparent image into a PDF? I'm trying to "sign" a PDF document by inserting an image of my signature, but even though every OSX and Windows PDF editor seems to support this, I haven't found any Linux PDF editors that do. I've tried PDFChain, PDF Editor, Flpsed PDF Annotator, Openoffice, Scribus, Krita, and PDFSam, and none support this. Although not technically a Linux program, I tried the site pdfescape.com, but it corrupts the images it inserts, rendering it useless for this task. Note, I'm talking about keeping the PDF in PDF format, so rasterizing it to a TIF/PNG/BMP, editing it in Gimp, and then dumping it back into a PDF isn't a solution. EDIT: I might have been premature in my criticism of pdfescape.com and PDF Editor. I was viewing the resulting PDF in Evince, which was showing a mangled image, but when I opened the PDF in PDF Editor, the image rendered correctly. I've since sent the PDF to someone on Windows who confirmed the image showed correctly. It looks like the problem might be inaccurate rendering with Evince.

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  • Speed up bitstring/bit operations in Python?

    - by Xavier Ho
    I wrote a prime number generator using Sieve of Eratosthenes and Python 3.1. The code runs correctly and gracefully at 0.32 seconds on ideone.com to generate prime numbers up to 1,000,000. # from bitstring import BitString def prime_numbers(limit=1000000): '''Prime number generator. Yields the series 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 ... using Sieve of Eratosthenes. ''' yield 2 sub_limit = int(limit**0.5) flags = [False, False] + [True] * (limit - 2) # flags = BitString(limit) # Step through all the odd numbers for i in range(3, limit, 2): if flags[i] is False: # if flags[i] is True: continue yield i # Exclude further multiples of the current prime number if i <= sub_limit: for j in range(i*3, limit, i<<1): flags[j] = False # flags[j] = True The problem is, I run out of memory when I try to generate numbers up to 1,000,000,000. flags = [False, False] + [True] * (limit - 2) MemoryError As you can imagine, allocating 1 billion boolean values (1 byte 4 or 8 bytes (see comment) each in Python) is really not feasible, so I looked into bitstring. I figured, using 1 bit for each flag would be much more memory-efficient. However, the program's performance dropped drastically - 24 seconds runtime, for prime number up to 1,000,000. This is probably due to the internal implementation of bitstring. You can comment/uncomment the three lines to see what I changed to use BitString, as the code snippet above. My question is, is there a way to speed up my program, with or without bitstring?

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