Search Results

Search found 6805 results on 273 pages for 'fast formula'.

Page 227/273 | < Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >

• rs232 communication, general timing question

  - by Sunny Dee

  Hi, I have a piece of hardware which sends out a byte of data representing a voltage signal at a frequency of 100Hz over the serial port. I want to write a program that will read in the data so I can plot it. I know I need to open the serial port and open an inputstream. But this next part is confusing me and I'm having trouble understanding the process conceptually: I create a while loop that reads in the data from the inputstream 1 byte at a time. How do I get the while loop timing so that there is always a byte available to be read whenever it reaches the readbyte line? I'm guessing that I can't just put a sleep function inside the while loop to try and match it to the hardware sample rate. Is it just a matter of continuing reading the inputstream in the while loop, and if it's too fast then it won't do anything (since there's no new data), and if it's too slow then it will accumulate in the inputstream buffer? Like I said, i'm only trying to understand this conceptually so any guidance would be much appreciated! I'm guessing the idea is independent of which programming language I'm using, but if not, assume it is for use in Java. Thanks!

  Read the article

• jquery toggle and fade in one function?

  - by tony noriega

  I was wondering if toggle() and fadeIn() could be used in one function... i got this to work, but it only fades in after the second click... not on first click of the toggle. $(document).ready(function() { $('#business-blue').hide(); $('a#biz-blue').click(function() { $('#business-blue').toggle().fadeIn('slow'); return false; }); // hides the slickbox on clicking the noted link $('a#biz-blue-hide').click(function() { $('#business-blue').hide('fast'); return false; }); }); <a href="#" id="biz-blue">Learn More</a> <div id="business-blue" style="border:1px soild #00ff00; background:#c6c1b8; height:600px; width:600px; margin:0 auto; position:relative;"> <p>stuff here</p> </div>

  Read the article

• C question: error: expected ')' before '*' token

  - by lhw

  ===EDIT I apologize for not putting the pcb struct into the code snippet. There is a struct called pcb defined in above the two structs I originally posted. Namely, typedef struct{ UINT32 proc; struct pcb *link; }pcb; Hi, I asked a question regarding structs in C a few minutes ago and got an answer blazing fast. But now I'm facing another problem, namely the error in the title of this question. I'm trying to implement a simple priority queue in C using arrays of queues. However, when I try to declare a function on pcb_pQ structure, I get the above error. I have the structs clearly defined in the heard file. In the header file: typedef struct{ pcb *head; pcb *tail; SINT32 size; } pcb_Q; typedef struct pcb_pQ { pcb_Q queues[5]; SINT32 size; } pcb_pQ; Function prototype in header file: /*priority queue operations*/ VOID pcb_pq_enqueue(pcb_pQ*, pcb*); Function impelmentation in .c file: VOID pcb_pq_enqueue(pcb_pQ* pcb_pQ, pcb* pcb) { pcb_Q* pcb_Q_p; int priority; priority = pcb->proc_priority; pcb_Q_p = &pcb_pQ->queues[priority]; pcb_enqueue(pcb_Q_p, pcb); } When I try to compile the above code, I get an "error: expected ')' before '*' token". This error is pointing to the function signature in the .c file, namely VOID pcb_pq_enqueue(pcb_pQ* pcb_pQ, pcb* pcb) { But I am not sure why I am getting this error, could someone give me a hand? Thanks a lot.

  Read the article

• Source of UIView Implicit Animation delay?

  - by iPhoneToucher

  I have a block of UIView animation code that looks like this: [UIView beginAnimations:@"pushView" context:nil]; [UIView setAnimationDelay:0]; [UIView setAnimationDuration:.5]; [UIView setAnimationDelegate:self]; [UIView setAnimationWillStartSelector:@selector(animationWillStart)]; view.frame = CGRectMake(0, 0, 320, 416); [UIView commitAnimations]; The code basically mimics the animation of a ModalView presentation and is tied to a button on my interface. When the button is pressed, I get a long (.5 sec) delay (on iPod Touch...twice as fast on iPhone 3GS) before the animationWillStart: actually gets called. My app has lots going on besides this, but I've timed various points of my code and the delay definitely occurs at this block. In other words, a timestamp immediately before this code block and a timestamp when animationWillStart: gets called shows a .5 sec difference. I'm not too experienced with Core Animation and I'm just trying to figure out what the cause of the delay is...Memory use is stable when the animation starts and CoreAnimation FPS seems to be fine in Instruments. The view that gets animated does have upwards of 20 total subviews, but if that were the issue wouldn't it cause choppiness after the animation starts, rather than before? Any ideas?

  Read the article

• List of objects or parallel arrays of properties?

  - by Headcrab

  The question is, basically: what would be more preferable, both performance-wise and design-wise - to have a list of objects of a Python class or to have several lists of numerical properties? I am writing some sort of a scientific simulation which involves a rather large system of interacting particles. For simplicity, let's say we have a set of balls bouncing inside a box so each ball has a number of numerical properties, like x-y-z-coordinates, diameter, mass, velocity vector and so on. How to store the system better? Two major options I can think of are: to make a class "Ball" with those properties and some methods, then store a list of objects of the class, e. g. [b1, b2, b3, ...bn, ...], where for each bn we can access bn.x, bn.y, bn.mass and so on; to make an array of numbers for each property, then for each i-th "ball" we can access it's 'x' coordinate as xs[i], 'y' coordinate as ys[i], 'mass' as masses[i] and so on; To me it seems that the first option represents a better design. The second option looks somewhat uglier, but might be better in terms of performance, and it could be easier to use it with numpy and scipy, which I try to use as much as I can. I am still not sure if Python will be fast enough, so it may be necessary to rewrite it in C++ or something, after initial prototyping in Python. Would the choice of data representation be different for C/C++? What about a hybrid approach, e.g. Python with C++ extension?

  Read the article

• Design considerations for temporarily transforming a player into an animal in a role playing game

  - by mikedev

  I am working on a role playing game for fun and to practice design patterns. I would like players to be able to transform themselves into different animals. For example, a Druid might be able to shape shift into a cheetah. Right now I'm planning on using the decorator pattern to do this but my question is - how do I make it so that when a druid is in the cheetah form, they can only access skills for the cheetah? In other words, they should not be able to access their normal Druid skills. Using the decorator pattern it appears that even in the cheetah form my druid will be able to access their normal druid skills. class Druid : Character { // many cool druid skills and spells void LightHeal(Character target) { } } abstract class CharacterDecorator : Character { Character DecoratedCharacter; } class CheetahForm : CharacterDecorator { Character DecoratedCharacter; public CheetahForm(Character decoratedCharacter) { DecoratedCharacter= decoratedCharacter; } // many cool cheetah related skills void CheetahRun() { // let player move very fast } } now using the classes Druid myDruid = new Druid(); myDruid.LightHeal(myDruid); // casting light heal here is fine myDruid = new CheetahForm(myDruid); myDruid.LightHeal(myDruid); // casting here should not be allowed Hmmmm...now that I think about it, will myDruid be unable to us the Druid class spells/skills unless the class is down-casted? But even if that's the case, is there a better way to ensure that myDruid at this point is locked out from all Druid related spells/skills until it is cast back to a Druid (since currently it's in CheetahForm)

  Read the article

• How do you handle your "Project Manager"

  - by Vecdid

  I currently work for a company who recently has downsized. I do all in house work, client installs, builds,q.a, well basically all the in house work. My direct boss is VERY untechnical and lately I have found it VERY hard to deal with his lack of knowledge. The biggest issues I have had are as follows: I am on many deadlines at a time. I get stopped to put together a half fast quote as I cannot be late on the deadline, in the meantime, three support calls comes in, I give quote, time too much so they outsource it. I then I have to fix everything the vendor broke. I get asked, when an issue arrises, why is the issue occurring and explain in detail, yet that detail means absolutly nothing to him. All he cares about are deadlines, yet he is the one who schdules everything. "I am a programmer not a graphic designer, meaqns nothing to him" I was hired as a .NET programmer, yet they let a vendor choose wordpress for many sites(yeah I had to learn all about it quick) I guess I can go on and on, but has anyone had to deal with this type of project manager? What is some advice, other than finding another job. Thanks in advance, and I made this a wiki, so please don't close...

  Read the article

• Telerik vs. Infragistics for Silverlight

  - by JeffN825

  Yes, this is certainly a duplicate question, but I wanted to get some fresh takes. My impression is that Telerik is a much more complete suite, but I'm really really turned off by the responsiveness of their controls. It just seems "clunky" in terms of responsiveness (I have a very fast computer and video card). Scrolling in a grid and transitions chunk, even in their latest demos where they claim to have good performance. I do like that their WPF suite matches their SL one in terms of API. Infragistics has fewer controls and less theming possibilities, but their controls are very responsive. Scrolling in a grid is fluid, as are their combo menus and all the other controls. I checked out ComponentOne and their controls seem analogous to Telerik's in terms of the points mentioned above but are a little less "pretty". Any thoughts from other users of these suites? Basically, what I'm looking for is a suite that will be highly performant and responsive, relatively customizable from a theming standpoint, and have enough functionality to develop a LOB SL application without having to use multiple suites to satisfy the majority of common requirements.

  Read the article

• Does Firefox on OS X Lion make use of Full Page Zoom for the touchpad? How to customize behavior?

  - by Steven Lu

  I really like the smooth pinch-zoom of Safari using the touchpad, but the two-finger scroll on Firefox is so much better than the scrolling performance in Safari. So I really like to use Firefox, but then I miss out on two-finger-double-tap to zoom to paragraph width, and the smooth pinch gesture zoom. What I'm wondering is if it is possible to write a Firefox Extension to improve the update rate of the full-page zoom in Firefox that is already functioning via the touchpad pinch gesture. I feel like it is specifically programmed to zoom at certain zoom levels: 100%, 120%, 150% (these are guesses of mine) but I think it would be great if I can get some more control there to make it work more like the zoom functionality in Safari. Also the two-finger-double-tap on a paragraph or element to zoom to it would be really awesome as well. https://developer.mozilla.org/en/Full_page_zoom This seems to indicate (if "full page zoom" is what I think it is) that an extension has the ability to zoom to an arbitrary scale factor, but what remains is to find out if it is possible to obtain or hook the touchpad pinch gesture. Update: I have updated the toolkit.zoomManager.zoomValues option in about:config to include more zoom levels: .3,.5,.67,.8,.9,1,1.01,1.02,1.03,1.04,1.05,1.06,1.07,1.08,1.09,1.1,1.2,1.33,1.5,1.7,2,2.4,3 Notice how I inserted a bunch of entries between 1 and 1.1. But it isn't switching between them any faster (why would it?) so it's less usable than before because of waiting for it to respond fast enough. It's clear that re-rendering the page at a different zoom level requires time and in order for the zoom to be dynamic, some kind of screen capture and scale effect must be performed (which is what Safari does). I guess such a thing is probably doable but I don't think I could pull it off. :-/

  Read the article

• HttpURLConnection inside a loop

  - by Carlos Garces

  Hi! I'm trying to connect to one URL that I know that exist but I don't know when. I don't have access to this server so I can't change anything to receive a event. The actual code is this. URL url = new URL(urlName); for(int j = 0 ; j< POOLING && disconnected; j++){ HttpURLConnection connection = (HttpURLConnection) url.openConnection(); int status = connection.getResponseCode(); if(status == HttpURLConnection.HTTP_OK || status == HttpURLConnection.HTTP_NOT_MODIFIED){ //Some work }else{ //wait 3s Thread.sleep(3000); } } Java not is my best skill and I'm not sure if this code is good from the point of view of performance. I'm opening a new connection every 3 seconds? or the connection is reused? If I call to disconnect() I ensure that no new connections are open in the loop, but... it will impact in performance?. Suggestions? What is the fast/best ways to know it a URL exist?

  Read the article

• Where to put data management rules for complex data validation in ASP.NET MVC?

  - by TheRHCP

  Hello, I am currently working on an ASP.NET MVC2 project. This is the first time I am working on a real MVC web application. The ASP.NET MVC website really helped me to get started really fast, but I still have some obscure knowledge concerning datamodel validation. My problem is that I do not really know where to manage my filled datamodel when it comes to complex validation rules. For example, validating a string field with a Regex is quite easy and I know that I just have to decorate my field with a specific attribute, so data management rules are implemented in the model. But if I have multiple fields that I need to validate which each other, for example multiple datetime that need to be correctly set following a specific time rule, where do I need to validate them? I know that I could create my own validation attributes, but sometimes validation ask a specific validation path which is to complex to be validated using attributes. This first question also leads me to a related question which is, is it right to validate a model in the controller? Because for the moment that is the only way I found for complex validation. But I find this a bit dirty and I feel it does not really fit a the controller role and much harder to test (multiple code path). Thanks.

  Read the article

• How to find Part Time development/IT work?

  - by Jonathan

  I've been working in the IT field now for 10 years. Originally trained as an Engineer, started out with C++ and have been a .Net specialist since beta. Currently seconded to a major city and working in the finance industry as freelance, I really feel like i've hit the glass ceiling. Have been contracting now for 5 years as the company politics and frustration of not being promoted and poor pay rises for excellent work but during the last decade of corporate cost cutting took its toll on my morale. Freelance made all the difference and i've had a very decorated career for good clients. What any Engineering student could ever dream of when starting out. The problem is, it doesn't particularly make me happy. It's good work, and i enjoy the problem solving aspects of it and having something to do each day. However there is always a large overhead of non-technical work and dealing with poor managers etc. I guess the Engineering was always a bit of a mistake i made the best out of, and now having 10 years behind a computer hasn't done wonders for my health or eye sight. In a nutshell i am in the process of retraining as a therapist and would like to open my own clinic. However, never having done this before, the fast pace IT skills outdate and the fact that all my experience and skills are non transferrable, i am a little worried. Any ideas how i can find part time IT work as i build up my business? (it's incredibly hard to find freelancing work that doesn't require long hours and overtime). Or other ideas to make the transition easier, and perhaps backout if it financially doesn't work/or i have enough marketing skills? I'd be interested to hear from people who have made a similar transition, successfully or unsuccessfully. Many thanks

  Read the article

• Yet another Python Windows CMD mklink problem ... can't get it to work!

  - by Felix Dombek

  OK I have just posted another question which outlined my program but the specific problem was different. Now, my program just stops working without any message whatsoever. I'd be grateful if someone could help me here. I want to create symlinks for each file in a directory structure, all in one large flat folder, and have the following code by now: # loop over directory structure: # for all items in current directory, # if item is directory, recurse into it; # else it's a file, then create a symlink for it def makelinks(folder, targetfolder, cmdprocess = None): if not cmdprocess: cmdprocess = subprocess.Popen("cmd", stdin = subprocess.PIPE, stdout = subprocess.PIPE, stderr = subprocess.PIPE) print(folder) for name in os.listdir(folder): fullname = os.path.join(folder, name) if os.path.isdir(fullname): makelinks(fullname, targetfolder, cmdprocess) else: makelink(fullname, targetfolder, cmdprocess) #for a given file, create one symlink in the target folder def makelink(fullname, targetfolder, cmdprocess): linkname = os.path.join(targetfolder, re.sub(r"[\/\\\:\*\?\"\<\>\|]", "-", fullname)) if not os.path.exists(linkname): try: os.remove(linkname) print("Invalid symlink removed:", linkname) except: pass if not os.path.exists(linkname): cmdprocess.stdin.write("mklink " + linkname + " " + fullname + "\r\n") So this is a top-down recursion where first the folder name is printed, then the subdirectories are processed. If I run this now over some folder, the whole thing just stops after 10 or so symbolic links. Here is the output: D:\Musik\neu D:\Musik\neu\# Electronic D:\Musik\neu\# Electronic\# tag & reencode D:\Musik\neu\# Electronic\# tag & reencode\ChillOutMix D:\Musik\neu\# Electronic\# tag & reencode\Unknown D&B D:\Musik\neu\# Electronic\# tag & reencode\Unknown D&B 2 The program still seems to run but no new output is generated. It created 9 symlinks for some files in the # tag & reencode and the first three files in the ChillOutMix folder. The cmd.exe Window is still open and empty, and shows in its title bar that it is currently processing the mklink command for the third file in ChillOutMix. I tried to insert a time.sleep(2) after each cmdprocess.stdin.write in case Python is just too fast for the cmd process, but it doesn't help. Does anyone know what the problem might be?

  Read the article

• Help with Neuroph neural network

  - by user359708

  For my graduate research I am creating a neural network that trains to recognize images. I am going much more complex than just taking a grid of RGB values, downsampling, and and sending them to the input of the network, like many examples do. I actually use over 100 independently trained neural networks that detect features, such as lines, shading patterns, etc. Much more like the human eye, and it works really well so far! The problem is I have quite a bit of training data. I show it over 100 examples of what a car looks like. Then 100 examples of what a person looks like. Then over 100 of what a dog looks like, etc. This is quite a bit of training data! Currently I am running at about one week to train the network. This is kind of killing my progress, as I need to adjust and retrain. I am using Neuroph, as the low-level neural network API. I am running a dual-quadcore machine(16 cores with hyperthreading), so this should be fast. My processor percent is at only 5%. Are there any tricks on Neuroph performance? Or Java peroformance in general? Suggestions? I am a cognitive psych doctoral student, and I am decent as a programmer, but do not know a great deal about performance programming.

  Read the article

• ASP.NET MVC on Cassini: How can I force the "content" directory to return 304s instead of 200s?

  - by Portman

  Scenario: I have an ASP.NET MVC application developed in Visual Studio 2008. There is a root folder named "Content" that stores images and stylesheets. When I run locally (using Cassini) and browse my application, every resource from the "Content" directory is always downloaded. Using Firebug, I can verify that the web server returns an HTTP 200 ("ok"). Desired: I would like for Cassini to return HTTP 304 ("not modified") instead of 200. This is the behavior when running the site under IIS7. Reasoning: The site I am working on has a large number of static resources (often as many as 40 per page). Browsing the site is very fast on IIS7, because these resources are (correctly) cached by the browser. However, browsing the site on my local machine is painfully slow. Pages that render in under 1 second on IIS7 take over 30 seconds to render on Cassini. It's actually faster for me to upload the entire website every few minutes and test from there. (Yes, I recognize that this is perverse and crazy.) So: how can I instruct/trick Cassini into treating the "Content" directory like IIS7 does?

  Read the article

• Eclipse on windows doesnt start

  - by sap

  I usually do all my java development on linux, using fedora package manager setting up a development environment is easy and fast. Now I have to start using windows but I never used it for java development and im having a few difficulties having it setup. So I downloaded and installed thye java 6 JDK (just the standard edition, not the EE) and installed it. Next I downloaded eclipse classic package, which doesnt have an installer, you just unzip it and run it. I had to add the java bin directory to the PATH variable, which I did. But when I start eclipse.exe I get this: http://img02.imagefra.me/img/img02/1/12/12/f_12c33ivd2m_c79c09f.jpg I already made a new environment variable called CLASSPATH and add the d:/java sdk/lib directory to it, but it the same thing. Am I missing something? Thanks. UPDATE: so i wrote the path to the java.exe on the eclipse.ini file (linking to jvm.dll didnt work) and now it just opens a console window for a few seconds and then closes (doesnt output anything). also launching it like: java -jar plugins/org.eclipse.equinox.launcher_1.0.0.v20070208a.jar make the vm work for about 1-2 seconds and then it returns, with no outputs. UPDATE2: i didnt know it was writting a log file, found it and read it and it said i was using GWT x32 libraries on a x64 VM, so i just downloaded an eclipse x64 version and it worked. i still had to use the .ini trick to say where the JVM is installed. thanks a lot for the help.

  Read the article

• Why does output of fltk-config truncate arguments to gcc?

  - by James Morris

  I'm trying to build an application I've downloaded which uses the SCONS "make replacement" and the Fast Light Tool Kit Gui. The SConstruct code to detect the presence of fltk is: guienv = Environment(CPPFLAGS = '') guiconf = Configure(guienv) if not guiconf.CheckLibWithHeader('lo', 'lo/lo.h','c'): print 'Did not find liblo for OSC, exiting!' Exit(1) if not guiconf.CheckLibWithHeader('fltk', 'FL/Fl.H','c++'): print 'Did not find FLTK for the gui, exiting!' Exit(1) Unfortunately, on my (Gentoo Linux) system, and many others (Linux distributions) this can be quite troublesome if the package manager allows the simultaneous install of FLTK-1 and FLTK-2. I have attempted to modify the SConstruct file to use fltk-config --cflags and fltk-config --ldflags (or fltk-config --libs might be better than ldflags) by adding them like so: guienv.Append(CPPPATH = os.popen('fltk-config --cflags').read()) guienv.Append(LIBPATH = os.popen('fltk-config --ldflags').read()) But this causes the test for liblo to fail! Looking in config.log shows how it failed: scons: Configure: Checking for C library lo... gcc -o .sconf_temp/conftest_4.o -c "-I/usr/include/fltk-1.1 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_THREAD_SAFE -D_REENTRANT" gcc: no input files scons: Configure: no How should this really be done? And to complete my answer, how do I remove the quotes from the result of os.popen( 'command').read()? EDIT The real question here is why does appending the output of fltk-config cause gcc to not receive the filename argument it is supposed to compile?

  Read the article

• WPF, C# - Making Intellisense/Autocomplete list, fastest way to filter list of strings

  - by user559548

  Hello everyone, I'm writing an Intellisense/Autocomplete like the one you find in Visual Studio. It's all fine up until when the list contains probably 2000+ items. I'm using a simple LINQ statement for doing the filtering: var filterCollection = from s in listCollection where s.FilterValue.IndexOf(currentWord, StringComparison.OrdinalIgnoreCase) >= 0 orderby s.FilterValue select s; I then assign this collection to a WPF Listbox's ItemSource, and that's the end of it, works fine. Noting that, the Listbox is also virtualised as well, so there will only be at most 7-8 visual elements in memory and in the visual tree. However the caveat right now is that, when the user types extremely fast in the richtextbox, and on every key up I execute the filtering + binding, there's this semi-race condition, or out of sync filtering, like the first key stroke's filtering could still be doing it's filtering or binding work, while the fourth key stroke is also doing the same. I know I could put in a delay before applying the filter, but I'm trying to achieve a seamless filtering much like the one in Visual Studio. I'm not sure where my problem exactly lies, so I'm also attributing it to IndexOf's string operation, or perhaps my list of string's could be optimised in some kind of index, that could speed up searching. Any suggestions of code samples are much welcomed. Thanks.

  Read the article

• Delphi, PGDac vs Zeos, Fetch, Lookup?

  - by durumdara

  Hi! I used Zeos to test to know: is ZTable uses fetch technics, or not? May in the future we migrate our lesser system to PGSQL, and this used now "Table" components (as BDE, but it have an SQL-like server). These tables use real cursors, a "Window" with N record, so lookup is very fast, because the Locate/Lookup is started on server, and only these N records are refreshed, no matter, how many records in the lookup table. PGSQL uses fetch technics as I know, and I tested it with a table (id int, name varchar(100)), and 1 million records. (I also trying this with mysql). The adapter is Zeos. ID, sec to find, allocated memory in bytes on client. MySQL 500000 2,761 113 196 344 1000000 3,214 225 471 232 313800 0,437 225 471 232 328066 0,468 225 471 232 276374 0,390 225 471 232 905984 1,264 225 471 232 260253 0,359 225 471 232 PGSQL 500000 3,042 113 188 184 1000000 3,744 225 463 064 313800 0,436 225 463 064 328066 0,452 225 463 064 276374 0,375 225 463 064 905984 1,295 225 463 064 260253 0,359 225 463 064 142023 0,203 225 463 064 As you see the records are fetched locally, this cause the 225 MB usage, and searches are slow a little, based where is the record we must find. I want to ask more things: a.) Is PGDAC have some technics to we can use the lookups without pay the fetch with memory and secs? b.) Or is PG ODBC driver can help in this problem with ADO? (As I know ADO can use server side cursors)? c.) Have anybody some experience with lookup tables, and performance? Is this critical question or it is not? (With client memory usage too). d.) If no chance to avoid fetch hell with lookups, what we can do? Server Side Joins, and unique code for Lookup field changing without real Lookup? Thanks for your help: dd

  Read the article

• Django LFS - custom views

  - by owca

  For all those ligthning fast shop users. I'm trying to implement my own first page view that will list all products from shop ( under '/' address). So I have a template : {% extends "lfs/shop/shop_base.html" %} {% block content %} <div id="najnowsze_produkty"> <ul> {% for obj in objects %} <li> {{ obj.name }} </li> {% endfor %} </ul> </div> {% endblock %} and then I've edited main shop view : from lfs.catalog.models import Category from lfs.catalog.models import Product def shop_view(request, template_name="lfs/shop/shop.html"): products = Product.objects.all() shop = lfs_get_object_or_404(Shop, pk=1) return render_to_response(template_name, RequestContext(request, { "shop" : shop, "products" : products })) but it just shows nothing. When I do Product.objects.all() query in shell I get results. Any ideas what could cause the problem ? Maybe I should filter products with 'active' status only ? But I'm not sure if it can influence all objects in any way.

  Read the article

• Building a News-feed that comprises posts "created by user's connections" && "on the topics user is following"

  - by aklin81

  I am working on a project of Questions & Answers website that allows a user to follow questions on certain topics from his network. A user's news-feed wall comprises of only those questions that have been posted by his connections and tagged on the topics that he is following(his expertise topics). I am confused what database's datamodel would be most fitting for such an application. The project needs to consider the future provisions for scalability and high performance issues. I have been looking at Cassandra and MySQL solutions as of now. After my study of Cassandra I realized that Simple news-feed design that shows all the posts from network would be easy to design using Cassandra by executing fast writes to all followers of a user about the post from user. But for my kind of application where there is an additional filter of 'followed topics', (ie, the user receives posts "created by his network" && "on topics user is following"), I could not convince myself with a good schema design in Cassandra. I hope if I missed something because of my short understanding of cassandra, perhaps, can you please help me out with your suggestions of how this news-feed could be implemented in Cassandra ? Looking for a great project with Cassandra ! Edit: There are going to be maximum 5 tags allowed for tagging the question (ie, max 5 topics can be tagged on a question).

  Read the article

• How to trace the connection pool in a Java Web application - DBMS_APPLICATION_INFO

  - by Cleiton Garcia

  Hello, I need improve the traceability in a Web Application that usually run on fixed db user. The DBA should have a fast access for the information about the heavy users that are degrading the database. 5 years ago, I implemented a .NET ORM engine which makes a log of user and the server using the DBMS_APPLICATION_INFO package. Using a wrapper above the connection manager with the following code: DBMS_APPLICATION_INFO.SET_MODULE('" + User + " - " + appServerMachine + "',''); Each time that a connection get a connection from the pool, the package is executed to log the information in the V$SESSION. Has anyone discover or implemented a solution for this problem using the Toplink or Hibernate? Is there a default implementation for this problem? I found here a solutions as I implemented 5 years ago, but I'd like to know with anyone have a better solution and integrated with the ORM. http://stackoverflow.com/questions/53379/using-dbmsapplicationinfo-with-jboss My application is above Spring, the DAO are implemented with JPA (using hibernate) and actually running directly in Tomcat, with plans to (next year) migrate to SAP Netwevare Application Server. Thanks.

  Read the article

• Trouble Shoot JavaScript Function in IE

  - by CreativeNotice

  So this function works fine in geko and webkit browsers, but not IE7. I've busted my brain trying to spot the issue. Anything stick out for you? Basic premise is you pass in a data object (in this case a response from jQuery's $.getJSON) we check for a response code, set the notification's class, append a layer and show it to the user. Then reverse the process after a time limit. function userNotice(data){ // change class based on error code returned var myClass = ''; if(data.code == 200){ myClass='success'; } else if(data.code == 400){ myClass='error'; } else{ myClass='notice'; } // create message html, add to DOM, FadeIn var myNotice = '<div id="notice" class="ajaxMsg '+myClass+'">'+data.msg+'</div>'; $("body").append(myNotice); $("#notice").fadeIn('fast'); // fadeout and remove from DOM after delay var t = setTimeout(function(){ $("#notice").fadeOut('slow',function(){ $(this).remove(); }); },5000); }

  Read the article

• How to improve performance of non-scalar aggregations on denormalized tables

  - by The Lazy DBA

  Suppose we have a denormalized table with about 80 columns, and grows at the rate of ~10 million rows (about 5GB) per month. We currently have 3 1/2 years of data (~400M rows, ~200GB). We create a clustered index to best suit retrieving data from the table on the following columns that serve as our primary key... [FileDate] ASC, [Region] ASC, [KeyValue1] ASC, [KeyValue2] ASC ... because when we query the table, we always have the entire primary key. So these queries always result in clustered index seeks and are therefore very fast, and fragmentation is kept to a minimum. However, we do have a situation where we want to get the most recent FileDate for every Region, typically for reports, i.e. SELECT [Region] , MAX([FileDate]) AS [FileDate] FROM HugeTable GROUP BY [Region] The "best" solution I can come up to this is to create a non-clustered index on Region. Although it means an additional insert on the table during loads, the hit isn't minimal (we load 4 times per day, so fewer than 100,000 additional index inserts per load). Since the table is also partitioned by FileDate, results to our query come back quickly enough (200ms or so), and that result set is cached until the next load. However I'm guessing that someone with more data warehousing experience might have a solution that's more optimal, as this, for some reason, doesn't "feel right".

  Read the article

• sybase - fails to use index unless string is hard-coded

  - by Garrett

  I'm using Sybase 12.5.3 (ASE); I'm new to Sybase though I've worked with MSSQL pretty extensively. I'm running into a scenario where a stored procedure is really very slow. I've traced the issue to a single SELECT stmt for a relatively large table. Modifying that statement dramatically improves the performance of the procedure (and reverting it drastically slows it down; i.e., the SELECT stmt is definitely the culprit). -- Sybase optimizes and uses multi-column index... fast!<br> SELECT ID,status,dateTime FROM myTable WHERE status in ('NEW','SENT') ORDER BY ID -- Sybase does not use index and does very slow table scan<br> SELECT ID,status,dateTime FROM myTable WHERE status in (select status from allowableStatusValues) ORDER BY ID The code above is an adapted/simplified version of the actual code. Note that I've already tried recompiling the procedure, updating statistics, etc. I have no idea why Sybase ASE would choose an index only when strings are hard-coded and choose a table scan when choosing from another table. Someone please give me a clue, and thank you in advance.

  Read the article

< Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >