Search Results

Search found 80052 results on 3203 pages for 'data load performance'.

Page 431/3203 | < Previous Page | 427 428 429 430 431 432 433 434 435 436 437 438  | Next Page >

  • receiving data from serialport stops when main form is minimized or moved

    - by Rahul
    Sir, I apologize if this is already covered somewhere. I did a search and find something which I have already implemented. I am developing an application which receives data from a device connected via serialport. I am using SerialPort datareceived event to capture data. I am to display data in text boxes of the main form. Data is received frequently. I used Timer to send command to the device, in response device send some data. Timer interval is 100 ms. In every 100 ms interval some command is sent and correspondingly data is received. I used Invoke function to update the GUI elements like TExtbox, labels etc. Everything is fine. All the elements are updating beautifully. But during receiving data if I make any change in main form like moving form, minimizing, maximizing, or clicking somewhere in the form, then data receiving stops. I couldnot find the reason why its happening ? I also changed the timer interval to 200,300,400,500 but same problem is there. Please tell me why its happening? And possible solution... Thanks In advance.... :)

    Read the article

  • Why are compilers so stupid?

    - by martinus
    I always wonder why compilers can't figure out simple things that are obvious to the human eye. They do lots of simple optimizations, but never something even a little bit complex. For example, this code takes about 6 seconds on my computer to print the value zero (using java 1.6): int x = 0; for (int i = 0; i < 100 * 1000 * 1000 * 1000; ++i) { x += x + x + x + x + x; } System.out.println(x); It is totally obvious that x is never changed so no matter how often you add 0 to itself it stays zero. So the compiler could in theory replace this with System.out.println(0). Or even better, this takes 23 seconds: public int slow() { String s = "x"; for (int i = 0; i < 100000; ++i) { s += "x"; } return 10; } First the compiler could notice that I am actually creating a string s of 100000 "x" so it could automatically use s StringBuilder instead, or even better directly replace it with the resulting string as it is always the same. Second, It does not recognize that I do not actually use the string at all, so the whole loop could be discarded! Why, after so much manpower is going into fast compilers, are they still so relatively dumb? EDIT: Of course these are stupid examples that should never be used anywhere. But whenever I have to rewrite a beautiful and very readable code into something unreadable so that the compiler is happy and produces fast code, I wonder why compilers or some other automated tool can't do this work for me.

    Read the article

  • MSSQL Server high CPU and I/O activity database tuning

    - by zapping
    Our application tends to be running very slow recently. On debugging and tracing found out that the process is showing high cpu cycles and SQL Server shows high I/O activity. Can you please guide as to how it can be optimised? The application is now about an year old and the database file sizes are not very big or anything. The database is set to auto shrink. Its running on win2003, SQL Server 2005 and the application is a web application coded in c# i.e vs2005

    Read the article

  • Hashtable is that fast

    - by Costa
    Hi s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]. Is the hash function of the java string, I assume the rest of languages is similar or close to this implementation. If we have hash-Table and a list of 50 elements. each element is 7 chars ABCDEF1, ABCDEF2, ABCDEF3..... ABCDEFn If each bucket of hashtable contains 5 strings (I think this function will make it one string per bucket, but let us assume it is 5). If we call col.Contains("ABCDEFn"); // will do 6 comparisons and discover the difference on the 7th. The hash-table will take around 70 operations (multiplication and additions) to get the hashcode and to compare with 5 strings in bucket. and BANG it found. For list it will take around 300 comparisons to find it. for the case that there is only 10 elements, the list will take around 70 operations but the Hashtable will take around 50 operations. and note that hashtable operations are more time consuming (it is multiplications). I conclude that HybirdDictionary in .Net probably is the best choice for that most cases that require Hashtable with unknown size, because it will let me use a list till the list becomes more than 10 elements. still need something like HashSet rather than a Dictionary of keys and values, I wonder why there is no HybirdSet!! So what do u think? Thanks

    Read the article

  • how to send data to server using python

    - by Apache
    hi experts, how data can be send to the server, for example i retrieve MAC address, so i want send to the server ( i.e 211.21.24.43:8080/data?mac=00-0C-F1-56-98-AD i found snippet from internet as below from urllib2 import Request, urlopen from binascii import b2a_base64 def b64open(url, postdata): req = Request(url, b2a_base64(postdata), headers={'Content-Transfer-Encoding': 'base64'}) return urlopen(req) conn = b64open("http://211.21.24.43:8080/data","mac=00-0C-F1-56-98-AD") but when run, File "send2.py", line 8 SyntaxError: Non-ASCII character '\xc3' in file send2.py on line 8, but no encoding declared; see http://www.python.org/peps/pep-0263.html for details can anyone help me how send data to the server thanks in advance

    Read the article

  • Migrate Data and Schema from MySQL to MSSQL

    - by colithium
    Are there any free solutions for automatically migrating a database from MySQL to MSSQL Server that "just works"? I've been attempting this simple (at least I thought so) task all day now. I've tried: MSSQL Server Management Studio's Import Data feature Create an empty database Tasks - Import Data... .NET Framework Data Provider for Odbc Valid DSN (verified it connects) Copy data from one or more tables or views Check 1 VERY simple table Click Preview Get Error: The preview data could not be retrieved. ADDITIONAL INFORMATION: ERROR [42000] [MySQL][ODBC 5.1 Driver][mysqld-5.1.45-community]You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '"table_name"' at line 1 (myodbc5.dll) A similar error occurs if I go through the rest of the wizard and perform the operation. The failed step is "Setting Source Connection" the error refers to retrieving column information and then lists the above error. It can retrieve column information just fine when I modify column mappings so I really don't know what the issue is. I've also tried getting various MySql tools to output ddl statements that MSSQL understand but haven't succeeded. I've tried with MySQL v5.1.11 to SQL Server 2005 and with MySQL v5.1.45 to SQL Server 2008 (with ODBC drivers 3.51.27.00 and 5.01.06.00 respectively)

    Read the article

  • Can this loop be sped up in pure Python?

    - by Noctis Skytower
    I was trying out an experiment with Python, trying to find out how many times it could add one to an integer in one minute's time. Assuming two computers are the same except for the speed of the CPUs, this should give an estimate of how fast some CPU operations may take for the computer in question. The code below is an example of a test designed to fulfill the requirements given above. This version is about 20% faster than the first attempt and 150% faster than the third attempt. Can anyone make any suggestions as to how to get the most additions in a minute's time span? Higher numbers are desireable. EDIT: This experiment is being written in Python 3.1 and is 15% faster than the fourth speed-up attempt. def start(seconds): import time, _thread def stop(seconds, signal): time.sleep(seconds) signal.pop() total, signal = 0, [None] _thread.start_new_thread(stop, (seconds, signal)) while signal: total += 1 return total if __name__ == '__main__': print('Testing the CPU speed ...') print('Relative speed:', start(60))

    Read the article

  • C++ & proper TDD

    - by Kotti
    Hi! I recently tried developing a small-sized project in C# and during the whole project our team used the Test-Driven-Development (TDD) technique (xunit, moq). I really think this was awesome, because (when paired with C#) this approach allowed to relax when coding, relax when projecting and relax when refactoring. I suspect that all this TDD-stuff actually simplifies the coding process and, well, it allowed (eventually, for me) to get the same result with fewer brain cells working. Right after that I tried using TDD paired with C++ (I used Google Test and Google Mock libraries), and, I don't know why but I actually think that TDD here was a step back in terms of rapid application development. I had some moments when I had to spend huge amounts of time thinking of my tests, building proper mocks, rebuilding them and swearing at my monitor. And, well, I obviously can't ask something like "what I did wrong?" or "what was wrong in my approach?", because I don't know what to describe. But if there are any people who are used to TDD in C++ (and, probably C#) too, could you please advise me how to do this properly. Framework recommendations, architecture approaches, plain coding advices - if you are experienced in TDD & C++, please respond.

    Read the article

  • Python: how to run several scripts (or functions) at the same time under windows 7 multicore processor 64bit

    - by Gianni
    sorry for this question because there are several examples in Stackoverflow. I am writing in order to clarify some of my doubts because I am quite new in Python language. i wrote a function: def clipmyfile(inFile,poly,outFile): ... # doing something with inFile and poly and return outFile Normally I do this: clipmyfile(inFile="File1.txt",poly="poly1.shp",outFile="res1.txt") clipmyfile(inFile="File2.txt",poly="poly2.shp",outFile="res2.txt") clipmyfile(inFile="File3.txt",poly="poly3.shp",outFile="res3.txt") ...... clipmyfile(inFile="File21.txt",poly="poly21.shp",outFile="res21.txt") I had read in this example Run several python programs at the same time and i can use (but probably i wrong) from multiprocessing import Pool p = Pool(21) # like in your example, running 21 separate processes to run the function in the same time and speed my analysis I am really honest to say that I didn't understand the next step. Thanks in advance for help and suggestion Gianni

    Read the article

  • Multiple winform data save problem

    - by Mahesh
    hi am using C# with VS-2005 I have a form1 and about two textBox and one Combobox on it. like below textBox1 texbox2 ComboBox I have bind combobox by sql database. first user type in textbox1 and textbox2 and then goes to comboBox in which "BuyerName" available on it. if user not found the data in the comboBox then press ALT+C for opening of Form2 where they create data and save it. My problem is when I closed the form2 by saving data of "BuyerName" the form1 is open as per my requirement but the data of textBox1 and textBox2 which user typed before opening of form2 is lost and therefore user have to re-type on it. which i don't want as it wasting of time. I want when form2 closed and form1 open the data will be available on it. and when u create fresh "BuyerName" from form2 the "BuyerName" will be automaticaly available on form1 comboBox on closing of form2. Hope u will get it. am new here in programing so kindly suggest me by proper codeing. thx in Advance.

    Read the article

  • how to merge ecommerce transaction data between two databases

    - by yamspog
    We currently run an ecommerce solution for a leisure and travel company. Everytime we have a release, we must bring the ecommerce site down as we update database schema and the data access code. We are using a custom built ORM where each data entity is responsible for their own CRUD operations. This is accomplished by dynamically generating the SQL based on attributes in the data entity. For example, the data entity for an address would be... [tableName="address"] public class address : dataEntity { [column="address1"] public string address1; [column="city"] public string city; } So, if we add a new column to the database, we must update the schema of the database and also update the data entity. As you can expect, the business people are not too happy about this outage as it puts a crimp in their cash-flow. The operations people are not happy as they have to deal with a high-pressure time when database and applications are upgraded. The programmers are upset as they are constantly getting in trouble for the legacy system that they inherited. Do any of you smart people out there have some suggestions?

    Read the article

  • RAII: Initializing data member in const method

    - by Thomas Matthews
    In RAII, resources are not initialized until they are accessed. However, many access methods are declared constant. I need to call a mutable (non-const) function to initialize a data member. Example: Loading from a data base struct MyClass { int get_value(void) const; private: void load_from_database(void); // Loads the data member from database. int m_value; }; int MyClass :: get_value(void) const { static bool value_initialized(false); if (!value_initialized) { // The compiler complains about this call because // the method is non-const and called from a const // method. load_from_database(); } return m_value; } My primitive solution is to declare the data member as mutable. I would rather not do this, because it suggests that other methods can change the member. How would I cast the load_from_database() statement to get rid of the compiler errors?

    Read the article

  • Speed up math code in C# by writing a C dll?

    - by Projectile Fish
    I have a very large nested for loop in which some multiplications and additions are performed on floating point numbers. for (int i = 0; i < length1; i++) { s = GetS(i); c = GetC(i); for(int j = 0; j < length2; j++) { double oldU = u[j]; u[j] = c * oldU + s * omega[i][j]; omega[i][j] = c * omega[i][j] - s * oldU; } } This loop is taking up the majority of my processing time and is a bottleneck. Would I be likely to see any speed improvements if I rewrite this loop in C and interface to it from C#?

    Read the article

  • Sharing [config] data across modules,functions

    - by williamstw
    I have some configuration data in a config file that I read off disk when the app starts. I need to make that configuration data available to other functions/modules in the application. I started down the path of looking into ets/mnesia to store the data on startup to make it shared among all processes, but then my inner voice cautioned me that there must be a more functional, erlang-y way to do this. The only alternate approach I've come up with so far is setting up a module that has an actor loop that reads the data on startup and responds to messages like {Key, From} and responds by From ! {ok,Value}. Then, I gave up and decided to ask... Thanks, --tim

    Read the article

  • getting data from dynamic schema

    - by coure2011
    I am using mongoose/nodejs to get data as json from mongodb. For using mongoose I need to define schema first like this var mongoose = require('mongoose'); var Schema = mongoose.Schema; var GPSDataSchema = new Schema({ createdAt: { type: Date, default: Date.now } ,speed: {type: String, trim: true} ,battery: { type: String, trim: true } }); var GPSData = mongoose.model('GPSData', GPSDataSchema); mongoose.connect('mongodb://localhost/gpsdatabase'); var db = mongoose.connection; db.on('open', function() { console.log('DB Started'); }); then in code I can get data from db like GPSData.find({"createdAt" : { $gte : dateStr, $lte: nextDate }}, function(err, data) { res.writeHead(200, { "Content-Type": "application/json", "Access-Control-Allow-Origin": "*" }); var body = JSON.stringify(data); res.end(body); }); How to define scheme for a complex data like this, you can see that subSection can go to any deeper level. [ { 'title': 'Some Title', 'subSection': [{ 'title': 'Inner1', 'subSection': [ {'titile': 'test', 'url': 'ab/cd'} ] }] }, .. ]

    Read the article

  • Select a data template by item type programatically in WPF

    - by Michael Stoll
    Hi all, unfortunately the WPF ToolbarTray does not support binding to a collection of ToolbarViewModels (Correct me, if I'm wrong). Thus I want to create the Toolbars programmatically. So there are two tasks, which I don't know how to do: Select the data template based on the item type. Instantiate the data template as toolbar Both should do the same as WPF does, when we use ItemsControl with an enumerable content and empty template. I used reflector to anaylse what WPF does. Task 1 is done by FrameworkElement.FindTemplateResourceInternal, but this is internal, and I couldn't find any public methods to acomplish the task. Of course one could enumerate all resources and match the data template data type property, but this seems sub-optimal. Who know's how to acomplish these tasks?

    Read the article

  • Understanding the passing of data/life of a script in web development/CodeIgniter

    - by Pete Jodo
    I hope I worded the title accurately enough but I typically use Java and don't have much experience in Web Development/PHP/CodeIgniter. I have a difficult time understanding the life cycle of a script as I found out trying to implement a certain feature to a website I am developing (as a means of learning how to). I'll first describe the feature I tried implementing and then the problem I ran into that made me question my fundamental understanding of how scripts work since I'm used to typical OOP. Ok so here goes... I have a webpage that has 2 basic tasks a user can do, create and delete an entry. What I attempted to implement was a way to time a user how long it takes them to complete a certain task. The way I did this was have a homepage where there would be a list of tasks a user to choose from (in this case 2, create and delete). A user would click a task which would link to the 'true' homepage where the user then would be expected to complete the task. My script looks like this: <?php class Site extends CI_Controller { var $task1; var $tasks = array( "task1" => NULL, "date1" => 0, "date2" => 0, "diff" => 0); function __construct() { parent::__construct(); include 'timetask.php'; $this->task1 = new TimeTask("create"); } function index() { $this->tasks['task1'] = $this->task1->getTask(); $this->tasks['diff'] = $this->task1->getTimeDiff(); if($this->tasks['diff'] == NULL) { $this->tasks['diff'] = 0; } $this->load->view('usability_test', $this->tasks); } function origIndex() { $this->task1->setDate1(new DateTime()); $this->tasks['date1'] = $this->task1->getDate1()->getTimestamp(); $data = array(); if($q = $this->site_model->get_records()) { $data['records'] = $q; } $this->load->view('options_view', $data); } function create() { $this->task1->setDate2(new DateTime()); $this->tasks['date2'] = $this->task1->getDate2()->getTimestamp(); $data = array( 'author' => $this->input->post('author'), 'title' => $this->input->post('title'), 'contents' => $this->input->post('contents') ); $this->site_model->add_record($data); $this->index(); } I only included create to keep it short. Then I also have the TimeTask class, that actually another StackOverflow so kindly helped me with: <?php class TimeTask { private $task; /** * @var DateTime */ private $date1, $date2; function __construct($currTask) { $this->task = $currTask; } public function getTimeDiff() { $hasDiff = $this->date1 && $this->date2; if ($hasDiff) { return $this->date2->getTimestamp() - $this->date1->getTimestamp(); } else { return NULL; } } public function __toString() { return (string) $this->getTimeDiff(); } /** * @return \DateTime */ public function getDate1() { return $this->date1; } /** * @param \DateTime $date1 */ public function setDate1(DateTime $date1) { $this->date1 = $date1; } /** * @return \DateTime */ public function getDate2() { return $this->date2; } /** * @param \DateTime $date2 */ public function setDate2(DateTime $date2) { $this->date2 = $date2; } /** * @return get current task */ public function getTask() { return $this->task; } } ?> I don't think posting the views is necessary for the question but here is atleast how the links are made. ...and... id", $row-title); ? Now there's no error in the code but it doesn't do what I expect of it and the reason I assume why is because that each time a function of the script is called via a new page it is NOT the same instance of the script called previously so any previously created objects are no longer there. This confuses me and leaves me quite unsure of how to implement this gracefully. Some ways I would guess of how to do this is by passing the necessary data through the URL or have data saved in a database and retrieve it later to compare the times. What would be a recommended way to do, not just this, but anything that needs previously created data? Also, am I correct to think that a script is only 'alive' for one webpage at a time? Thanks!

    Read the article

  • How to prepare data for display on a silverlight chart using WCF RIA Services + Entity Framework

    - by Banford
    I've used WCF RIA services with Entity Framework to build a simple application which can display and updates data about school courses. This was done by following the Microsoft tutorials. Now I would like to have a chart which shows a count for how many courses are on a key stage. Example: Key Stage 3 - 20 courses Key Stage 4 - 32 courses Key Stage 5 - 12 courses Displayed on any form of chart. I have no problem binding data to the chart in XAML. My problem is that I do not know how to correct way of getting the data into that format. The generated CRUD methods are basic. I have a few thoughts about possible ways, but don't know which is correct, they are: Create a View in SQL server and map this to a separate Entity in the Entity Data Model. Generating new CRUD methods for this automatically. Customise the read method in the existing DomainService using .Select() .Distinct() etc. Don't know this syntax very well labda expressions/LINQ??? what is it? Any good quickstarts on it? Create a new class to store only the data required and create a read method for it. Tried this but didn't know how to make it work without a matching entity in the entity model. Something I am not aware of. I'm very new to this and struggling with the concepts so if there are useful blogs or documentation I've missed feel free to point me towards them. But I'm unsure of the terminology to use in my searches at the moment.

    Read the article

  • Validate data before uploading through SSIS

    - by The King
    I have a SSIS package to upload data from Excel file into an Sql Server 2005 table. The excel file will have varied lines of data ranging from 20k - 30k lines. The upload works fine, when all the data are correct. But obviously fails when there is a small problem even in a single row. Examples like mandatory values presented null, inconvertable values (data type mismatch) etc. I want to validate the excel file before the upload and want to tell the user which row and column has got the error... Any idea as to how to accomplish this, without consuming much time and resources. Thanks

    Read the article

  • Insert a Join Statement - (Insert Data to Multiple Tables) - C#/SQL/T-SQL/.NET

    - by peace
    I have a Winform that has fields need to be filled by a user. All the fields doesn't belong to one table, the data will go to Customer table and CustomerPhone table, so i decided to do multiple inserts. I will insert appropriate data to CustomerPhone first then Insert the rest data to Customer table. Is it possible to Join an Insert OR Insert a Join? If show me a rough sample, i will be grateful. Many Thanks

    Read the article

  • Why are difference lists more efficient than regular concatenation?

    - by Craig Innes
    I am currently working my way through the Learn you a haskell book online, and have come to a chapter where the author is explaining that some list concatenations can be ineffiecient: For example ((((a ++ b) ++ c) ++ d) ++ e) ++ f Is supposedly inefficient. The solution the author comes up with is to use 'difference lists' defined as newtype DiffList a = DiffList {getDiffList :: [a] -> [a] } instance Monoid (DiffList a) where mempty = DiffList (\xs -> [] ++ xs) (DiffList f) `mappend` (DiffList g) = DiffList (\xs -> f (g xs)) I am struggling to understand why DiffList is more computationally efficient than a simple concatenation in some cases. Could someone explain to me in simple terms why the above example is so inefficient, and in what way the DiffList solves this problem?

    Read the article

  • Tuning JVM (GC) for high responsive server application

    - by elgcom
    I am running an application server on Linux 64bit with 8 core CPUs and 6 GB memory. The server must be highly responsive. After some inspection I found that the application running on the server creates rather a huge amount of short-lived objects, and has only about 200~400 MB long-lived objects(as long as there is no memory leak) After reading http://java.sun.com/javase/technologies/hotspot/gc/gc_tuning_6.html I use these JVM options -Xms2g -Xmx2g -XX:MaxPermSize=256m -XX:NewRatio=1 -XX:+UseConcMarkSweepGC Result: the minor GC takes 0.01 ~ 0.02 sec, the major GC takes 1 ~ 3 sec the minor GC happens constantly. How can I further improve or tune the JVM? larger heap size? but will it take more time for GC? larger NewSize and MaxNewSize (for young generation)? other collector? parallel GC? is it a good idea to let major GC take place more often? and how?

    Read the article

  • How can I detect 'any' ajax request being completed using jQuery?

    - by Brian Scott
    I have a page where I can insert some javascript / jquery to manipulate the output. I don't have any other control over the page markup etc. I need to add an extra element via jquery after each present on the page. The issue is that the elements are generated via an asynchronous call on the existing page which occurs after $(document).ready is complete. Essentially, I need a way of calling my jquery after the page has loaded and the subsequent ajax calls have completed. Is there a way to detect the completion of any ajax call on the page and then call my own custom function to insert the additional elements after the newly created s ?

    Read the article

< Previous Page | 427 428 429 430 431 432 433 434 435 436 437 438  | Next Page >