Im trying to learn how to use a Parallel.For loop. Ive got a big for loop, that i need to run parallel, and am trying to use a Parallel.For loop for the first time. When I try using this code, I get that it cant be called using these arguments. The old way to write this would be:[code]I dont need to return anything to the for loop, Im just trying to iterate m, running in parallel. Where am I going wrong?
View 5 RepliesI'm trying to implement parallel computing using .NET 4 on an asp.net website housed on a clustered server consisting of 6-8 dual core servers. My original script contains two nested For...Next loops iterating through a range of values in a grid of x by y.
For each point in the grid (x,y), we should perform a computationally intensive subroutine called MakePartsMatrix which accesses a SQL server database with dataviews and manipulating the local variable "unfilled" which is passed in ByRef.
Without the parallel implementation, the nested for loops work fine except its slow -- taking about 60 seconds to run.
When I parallelize the outer For loop, the script is about 50% faster, completing its calculations in 20-30 seconds which is great. However, I have noticed that the parallelization causes random parts of the grid to be either completely skipped (eg, grid (1,5) is never evaluated by the MakePartsMatrix), or some points in the grid (eg, x=10 & y=5) to be evaluated multiple times, resulting in duplicate work.
When I parallelized only the inner For Loop, the script execution time also improves by 50%, but now the last row (y-1) in the grid is skipped entirely and the results in "unfilled" are completely wrong.
When I comment out the "MakePartsMatrix" subroutine, the parallellization (either inner or outer For loops) does appear to visit every point of the grid (x,y) once, and only once.
Dim ConcurrentListofResults As ConcurrentQueue(Of FindBestResults)
ConcurrentListofResults = New ConcurrentQueue(Of FindBestResults)
Dim FBSResultsItem As FindBestResults
[Code].....
I have a service that scans network folders using a parallel.for method. However recently I am finding if I stop the service then while windows says the service is stopped the process is still running in task manager. However it is at 0 cpu and the memory does not change. If I try and end the task (even a force in command prompt) it just says access denied and i have to reboot the server. What would be the best way to make sure everything terminates? I thought of adding a global Boolean that in the stop procedure it turns true and part of my parallel code will check for that and call s.stop.
View 1 Repliesthe purpose of the program is to display the monthly payments on the loan.My homework is to use do while loops instead of for loop.Here is the code for the for loop.
Option Explicit On
Option Strict On
Option Infer Off
[code].....
Now I'm having some trouble displaying the output using the do while loop, and I'm pretty sure it's a loop problem on my code. However, I cannot seemed to find out what's wrong. I looked at the examples of do while loop in my textbook, but I couldn't find anything useful to my problems of my program.This is the output for the do while loop.
Here's the do while loop code
Option Explicit On
Option Strict On
Option Infer Off
[code].....
When I use a For loop in a For loop the Contains Statement dosen't work! Even my custom one! I even tested mine and it works 100% And neither that or the String.Contains function work inside of For Loops And, I know both of them use loops to search through a string.
My function(It will atleast search once):
Function RealContains(ByVal load As String, ByVal needle As String) As Boolean
load = load.ToLower
[CODE].....................
I am work on VB.net 2003 Framework 1.1 for last 3.5 years in windows Application.We are currently migrating to VB.net 2008 framework 3.5, but i don't know about the features which related to ADO.net and which is important to performance. I know linq to SQL but our architecture is made in .net 2003 so we should follow this.Any features which is very important to enhance the performance?
View 2 RepliesI have a solution that I wish to upgrade from Vb.net framework 1.1 to framework 4.0. The solution consists of a number of projects, all but one of which compile to dll's. The master project compiles to a executable which provides a menuing system which dynamically loads the dll's and connects to entry points.
The projects contain normal classes, numbers of forms and also controls, which are either usercontrols or are inherited extensions of standard windows controls.There are a number of third party components (eg reporting and grid controls from Component One, Ribbon control from DevExpress etc).
[Code]...
How come software created in an older framework version won't run on a newer framework version? Actually whenever i try to run some old specific software having .net 3.5 framework on my PC they show they needs .net framwork 1.1 . What a bad thing?My newer version of Photoshop ans Ms office open all lower version files.
View 6 RepliesI have a 5 by 5 matrix I want to populate and I would like to simplify this into for loops. As I understand, I would need 2 for loops to complete this task?
Dim x(4, 4) As Char
x(0, 0) = Mid(key, 1, 1)
x(0, 1) = Mid(key, 2, 1)
x(0, 2) = Mid(key, 3, 1)
[code]....
EDIT:I have a ItemList : Dim ItemList As New List(Of String)I wanna append each element from itemlist to a new list for 10 times each, then to start over again.How can I make a loop for each element while there are still elements in the list (10 times each)?I tried this but it's not working.
Private crt As Integer = 0
Private limit As Integer = 0
Private Function getline() As String
Dim line As String = ""
[code]....
but I didn't know where to add the 10 times limit and also the current item number(crt)
im using tasks parallel library in .net 4.0 i want to have the ability to specify a task for each core independant of the other cores. usually in TPL, i create a task and i tell it to run in parallel, i have no control over the number of threads created nor can i control the number of cores to participate in the parallel task. also, i cant specify each particular core a different task.i'd like to know how to achieve this in TPL if it is possible.
View 3 RepliesIs there any way of doing parallel processing in VB.net. Like running a IF-ELSE and CASE in parallel.
For example i'm incrementing a counter in a IF-ELSE statement. And for each count i need to display some thing using a case statement.
tell how to form this to the correct Syntax?ere the sample in sequential form:ForEach ctrl AsCheckBoxIn tblCKBoxCollection.Controlsctrl.Checked =
View 1 RepliesI have been reading up on the parallel programming and even now still a little confused on the whole concepts. Lets say I have a single project with about 5 classes that interact and have local variables in methods and variables accessible to all methods in a single class and even 1 or 2 variables accessible to all classes accessed through instantiation. Now using threads I know that global variables would be overridden by multiple threads if there were no locking applied but local variables to a method/function do not, right?
So if I ran the project multiple times meaning as a new process, the methods and variables would be thread safe right and no data corruption occurs? So to implement parallel programming using the task factory, if I created a project that basically creates tasks and each task is basically running an instance of another project, then shouldn't the variables and data be thread safe and safe from corruption? But what if I had the output files and they named by Output & datetime.now.tostring, would there be conflict issues and I ask this knowing that I have seen this happen when trying it. [Code]
I'm writing a super small interpreter in vb.net because i need to execute a simple (invented) language so the app understand it and do what ever it needs to do.Everything went well until i reached the control structures and the loops.So my question its, in a code that its executed line by line using a simple for each how can i match the "WHILE ;" AND "ENDWHILE;" and execute the code within it?
The first thing that came to my mind its kind of flag the line of the reader and read the content from that line until find "ENDWHILE;" and the store that to execute late, so keep isolating the code in parts until I've all parts and then execute it.But i'm not so sure how to code it or if my reasoning its correct.PD: I'm using regexs.
I did For each Loop in my combobox, but I noticed that it loops twice. When it reaches the last item, it loops back to the first item. I code it typically: For each itm As Object in combobox.Items
[Code]....
have a problem where I have an application that allows someone to enter two integers. The app then displays all the odd numbers between both integers and all of the even numbers between both integers. There are two text boxes and two labels: even and odd. How would I code a For..Next loop for this type of app. The part where I get confused is what do I determine and how do I
View 18 RepliesI would like to simplify a do loop.
View 1 RepliesThis is for .net frameworke 3.5 and visual studio 2008 in VB.Net.Two things we would like to do: 1) loop repeating node blocks 2) loop (through repeating node blocks) within repeating node block loop
First thing:
How do you loop through an xml that has repeating node block (<STRUS name="1000A") and extract the following node? For example you want to extract the IdentificationCode in the node that has <SVALU name="ZRT" and is from pos="9".So, the following example has the IdentificationCodes (TGJ23, PGA12, TPX12)
<?xml version="1.0" encoding="UTF-8"?>
<DocSplitterReport xmlns:xsi="http://www.w3.org/2001/X .......
<STRUS name="ROOT" lineStart="-1" lineEnd="-1">
<STRUS name="TAC" lineStart="1" lineEnd="194">
<SVALUs>
[Code]...
Is it possible to merge two For Loops into one? I need this because I am using two for loops (1 to 100,000) to work with the data in a collection. The problem with this code is that it takes more than two hours two finish:
[Code]...
Is there a more efficient way of doing this code?
For Each row As DataRow In dt.Rows
Dim ts1 As String = row(0).ToString
For index As Integer = 1 To 9[code]....
Im somewhat new to VB, my first time writing a mildly long program... have a program that will create an unknown number of textboxes, then later I will need it to manipulate those textboxes. I set it up so it names them txt1, txt2, txt3 etc..How can I write a loop that will refer to each of these textboxes by name so I can do what I need with them, ie for example in
For i =1 to x
txti.text = i
next
this would make no sense...how do i write the names correctly so the computer can understate and loop them as txt1, txt2,...?
I have 2 threads in my Program. Here is code for both of them
Private Sub btnStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStart.Click
[Code]...
StartReceiving is working fine but StartWriting is called only once and that msgbox in startWriting is never called, any suggestions on this
I have this sub :
Private Sub error_out(ByVal line As Integer, ByVal err_col As Integer, ByVal err_msg As String)
Dim ln = t_erori.Rows.Add
[Code]....
I suspect this is because it's trying to add the same row twice.
How can i make this work ? Or what else method could I use to do this ?
I need this datatable because my app is writing some results in there, but any other method to store the results that works with parallel.for would be ok.
I have a class written in C#. In it I want to run a certain function in parallel on a list. After it completes on each item I would like to update a progress bar. However, I get very odd behavior from my program. It executes the event and reaches my sub but never proceeds to actually execute any code. Instead it just freezes. (I've mixed vb.net and c#. It will be rewritten at some point)[code]So for some reason I get it to enter progressBar Counter on each item in the list but it never exists. Instead it just keeps the form frozen.
View 2 RepliesI use the following code to print to the receipt printer on the parallel port in vb 6.0, but it seems that it doesn't work on vb.net.[code]...
View 2 RepliesI have two System.Windows.Forms.Timer with different interval having [code]...
but some timer2 not start wroking until timer1 not get finished i want them to run parallel without waiting for each other to finish
how can i sort too parallel arrays?
[Code]....
Those are the two arrays now when i try array.sort(strflavor,decamountsold) or array.sort(decamountsold,strflavor) they are not arraigned properly. I am trying to get them to sort by which flavor sold the least and which flavor sold the most. However when i sort them, the flavors are not matching up with the decimal values.
I prepare data to be processed, and saved to file. Since this process is slow, I want to delegate it to a parallel thread, so the main routine can end his work faster. The data is processed and saved to file by the "Sub ProcesarDatos", a routine on his instance of "FileProcessor class".
I call the code this way:
Dim
fp As
New
FileProcessor(DatosDeArchivo, Archivo & ".txt", Me)
ThreadPool.QueueUserWorkItem
(NewSystem.Threading.WaitCallback _
AddressOffp.ProcesarDatos))
i am trying to make a robot that i can talk to(not yet) and tell it to goto places 1st task it to figure out how to use an inbuilt webcam in my net book and do an image Recognition for walls stars eg 2nd task is to see if i can get it to use my server to help compute the images because my net book is very slow 3rd is speech to text now can all of these be done in vb.net?
View 2 Replies