Search Results

Search found 6241 results on 250 pages for 'unsigned integer'.

Page 222/250 | < Previous Page | 218 219 220 221 222 223 224 225 226 227 228 229  | Next Page >

  • Faster Insertion of Records into a Table with SQLAlchemy

    - by Kyle Brandt
    I am parsing a log and inserting it into either MySQL or SQLite using SQLAlchemy and Python. Right now I open a connection to the DB, and as I loop over each line, I insert it after it is parsed (This is just one big table right now, not very experienced with SQL). I then close the connection when the loop is done. The summarized code is: log_table = schema.Table('log_table', metadata, schema.Column('id', types.Integer, primary_key=True), schema.Column('time', types.DateTime), schema.Column('ip', types.String(length=15)) .... engine = create_engine(...) metadata.bind = engine connection = engine.connect() .... for line in file_to_parse: m = line_regex.match(line) if m: fields = m.groupdict() pythonified = pythoninfy_log(fields) #Turn them into ints, datatimes, etc if use_sql: ins = log_table.insert(values=pythonified) connection.execute(ins) parsed += 1 My two questions are: Is there a way to speed up the inserts within this basic framework? Maybe have a Queue of inserts and some insertion threads, some sort of bulk inserts, etc? When I used MySQL, for about ~1.2 million records the insert time was 15 minutes. With SQLite, the insert time was a little over an hour. Does that time difference between the db engines seem about right, or does it mean I am doing something very wrong?

    Read the article

  • Indy client receive string

    - by Eszee
    Im writing an Indy chat app, and am wondering if there is a way for the server component to tell the client that there is a string waiting, or even a way for the client to have an "OnExecute" like event. This is what i have now: server: procedure TServer.ServerExecute(AContext: TIdContext); var sResponse: string; I: Integer; list: Tlist; begin List := Server.Contexts.LockList; sResponse:= AContext.Connection.Socket.ReadLn; try for I := 0 to List.Count-1 do begin try TIdContext(List[I]).Connection.IOHandler.WriteLn(sResponse); except end; end; finally Server.Contexts.UnlockList; end; end; Client: procedure TForm1.Button1Click(Sender: TObject); var sMsg : string; begin Client.Socket.WriteLn(edit1.Text); sMsg := Client.Socket.ReadLn; Memo1.Lines.Add(sMsg); end; The problem is when i have 2 or more clients running the messages keep stacking because the button only processes 1 message a time. I'd like a way for the client to wait for messages and when it is triggered it processes those messages, like it does now under the button procedure. I've tried to put the "readln" part under a timer, but that causes some major problems. Im Using Delphi 2010 and Indy 10

    Read the article

  • How to create a generic method in C# that's all applicable to many types - ints, strings, doubles et

    - by satyajit
    Let's I have a method to remove duplicates in an integer Array public int[] RemoveDuplicates(int[] elems) { HashSet<int> uniques = new HashSet<int>(); foreach (int item in elems) uniques.Add(item); elems = new int[uniques.Count]; int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } How can I make this generic such that now it accepts a string array and remove duplicates in it? How about a double array? I know I am probably mixing things here in between primitive and value types. For your reference the following code won't compile public List<T> RemoveDuplicates(List<T> elems) { HashSet<T> uniques = new HashSet<T>(); foreach (var item in elems) uniques.Add(item); elems = new List<T>(); int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } The reason is that all generic types should be closed at run time. Thanks for you comments

    Read the article

  • C++ STL Map vs Vector speed

    - by sub
    In the interpreter for my experimental programming language I have a symbol table. Each symbol consists of a name and a value (the value can be e.g.: of type string, int, function, etc.). At first I represented the table with a vector and iterated through the symbols checking if the given symbol name fitted. Then I though using a map, in my case map<string,symbol>, would be better than iterating through the vector all the time but: It's a bit hard to explain this part but I'll try. If a variable is retrieved the first time in a program in my language, of course its position in the symbol table has to be found (using vector now). If I would iterate through the vector every time the line gets executed (think of a loop), it would be terribly slow (as it currently is, nearly as slow as microsoft's batch). So I could use a map to retrieve the variable: SymbolTable[ myVar.Name ] But think of the following: If the variable, still using vector, is found the first time, I can store its exact integer position in the vector with it. That means: The next time it is needed, my interpreter knows that it has been "cached" and doesn't search the symbol table for it but does something like SymbolTable.at( myVar.CachedPosition ). Now my (rather hard?) question: Should I use a vector for the symbol table together with caching the position of the variable in the vector? Should I rather use a map? Why? How fast is the [] operator? Should I use something completely different?

    Read the article

  • mysql_affected_rows() returns 0 for UPDATE statement even when an update actually happens

    - by Alex Moore
    I am trying to get the number of rows affected in a simple mysql update query. However, when I run this code below, PHP's mysql_affected_rows() always equals 0. No matter if foo=1 already (in which case the function should correctly return 0, since no rows were changed), or if foo currently equals some other integer (in which case the function should return 1). $updateQuery = "UPDATE myTable SET foo=1 WHERE bar=2"; mysql_query($updateQuery); if (mysql_affected_rows() > 0) { echo "affected!"; } else { echo "not affected"; // always prints not affected } The UPDATE statement itself works. The INT gets changed in my database. I have also double-checked that the database connection isn't being closed beforehand or anything funky. Keep in mind, mysql_affected_rows doesn't necessarily require you to pass a connection link identifier, though I've tried that too. Details on the function: mysql_affected_rows Any ideas? SOLUTION The part I didn't mention turned out to be the cause of my woes here. This PHP file was being called ten times consecutively in an AJAX call, though I was only looking at the value returned on the last call, ie. a big fat 0. My apologies!

    Read the article

  • Type of member is not CLS-compliant

    - by John Galt
    Using Visual Studio 2008 and VB.Net: I have a working web app that uses an ASMX web service which is compiled into its separate assembly. I have another class library project compiled as a separate assembly that serves as a proxy to this web service. This all seems to work at runtime but I am getting this warning at compile time which I don't understand and would like to fix: Type of member 'wsZipeee' is not CLS-compliant I have dozens of webforms in the main project that reference the proxy class with no compile time complaints as this snippet shows: Imports System.Data Partial Class frmZipeee Inherits System.Web.UI.Page Public wsZipeee As New ProxyZipeeeService.WSZipeee.Zipeee Dim dsStandardMsg As DataSet Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load And yet I have one webform (also in the root of the main project) which gives me the "not CLS-compliant" message but yet attempts to reference the proxy class just like the other ASPX files. I get the compile time warning on the line annoted by me with 'ERROR here.. Imports System.Data Partial Class frmHome Inherits System.Web.UI.Page Public wsZipeee As New ProxyZipeeeService.WSZipeee.Zipeee ERROR here Dim dsStandardMsg As DataSet Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load This makes no sense to me. The file with the warning is called frmHome.aspx.vb; all others in the project declare things the same way and have no warning. BTW, the webservice itself returns standard datatypes: integer, string, and dataset.

    Read the article

  • VB.net avoiding cross thread exception with extension method

    - by user574632
    Hello I am trying to implement a solution for updating form controls without using a delegate. I am attempting to use the 1st solution on this page: http://www.dreamincode.net/forums/blog/143/entry-2337-handling-the-dreaded-cross-thread-exception/ Imports System.ComponentModel Imports System.Runtime.CompilerServices Public Module MyInvoke <Extension()> _ Public Sub CustomInvoke(Of T As ISynchronizeInvoke)(ByVal control As T, ByVal toPerform As Action(Of T)) If control.InvokeRequired Then control.Invoke(toPerform, New Object() {control}) toPerform(control) End If End Sub End Module The site gives this as example of how to use: Label1.CustomInvoke(l => l.Text = "Hello World!") But i get 'l' is not declared error. As you can see im very new to VB or any OOP. I can get the second solution on that page to work (using delegates) but i have quite a few things to do in this thread and it seems like i would need to write a new delegate sub for each thing, which seems wasteful. What i need to do is select the 1st item from a combobox, update a textbox.text with the selected item, and pass the selected item to a function. Then wait for x seconds and start again, selecting the second item. I can get it to work in a single threaded application, but i need the interface to remain responsive. Any help greatly appreciated. EDIT: OK so changing the syntax worked for the example. However if i change it from Label1.CustomInvoke(Sub(l) l.text = "hello world!") (which worked just fine) to: Dim indexnumber As Integer = 0 ComboBox1.CustomInvoke(Sub(l) l.SelectedIndex = indexnumber) I get a cross threading error as though i didnt even use this method: Cross-thread operation not valid: Control 'ComboBox1' accessed from a thread other than the thread it was created on. So now im back to where i started? Any further help very much appreciated.

    Read the article

  • Defining multiple possibilities for the same element

    - by moggi
    Hello, is it possible in XML Schema to define the same element with several different definitions depending on one attribute. As Example: <xsd:element name="Element"> <xsd:complexType> <xsd:sequence> <xsd:attribute name="type" fixed="type1"/> <xsd:seqeuence> </xsd:complexType> </xsd:element> <xsd:element name="Element"> <xsd:complexType> <xsd:sequence> <xsd:attribute name="type" fixed="type2"/> <xsd:attribute name="value" type="xsd:integer"/> <xsd:seqeuence> </xsd:complexType> </xsd:element> <xsd:element name="RootElement"> <xsd:complexType> <xsd:sequence> <xsd:element ref="Element"/> </xsd:sequence> </xsd:complexType> </xsd:element> Or is there any other way to solve this problem. It is important that both definitions are named "Element", because I have an application needing that both elements are named the same way. But there is a second application that needs the additional information for type2.

    Read the article

  • how to add data to ARRAYLIST

    - by Chamal
    try { ArrayList ar=new ArrayList(); PRIvariable pri=new PRIvariable(); BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream("C:/cdr2.csv"))); while (reader.ready()) { String line = reader.readLine(); String[] values = line.split(","); pri.dateText=values[2]+" "+values[4]; pri.count=pri.count+1; pri.sum = pri.sum+Integer.parseInt(values[7]); System.out.println(pri.dateText+" "+pri.sum+" "+pri.count); ar.add(pri); } String[] columnNames={"Date","TOTAL","COUNTS"}; String[][] cells=new String[ar.size()][3]; for(int i=0;i<ar.size();i++){ cells[i][0]=((PRIvariable)ar.get(i)).dateText; cells[i][1]=""+((PRIvariable)ar.get(i)).sum; cells[i][2]=""+((PRIvariable)ar.get(i)).count; } table = new JTable(cells,columnNames); table.setSize(400,400); table.setVisible(true); JScrollPane js=new JScrollPane(); js.setViewportView(table); js.setSize(400,400); js.setVisible(true); add(js,java.awt.BorderLayout.CENTER); } catch (Exception e) { System.out.println(e); } This is my code. Here i want to Read text file and put that data to Jtable. But in this code it shows every row of the Jtable filled with same data that contain in arraylist(ar) last row. ( i think there is problem in my arraylist). How can i solve this......

    Read the article

  • visual studio 2008 (VB)

    - by Ousman
    hello guys, Am writing a programming with visual basic 2008 and i want the programme to be able to read and loop through a text file line by line and showing the event of the loop on a textbox or label until a button is press and the loop will stop on any number that happend to be at the loop event and when a button is press again the loop will continue from where it starts. this is my codes below and having problem with it and any help will be really great. tanks ==========================my codes======================= Imports System.IO '========================================================================================== Public Class Form1 '====================================================================================== 'Dim nFileNum As Integer = FreeFile() ' Get a free file number Dim strFileName As String = "C:\scb.txt" Dim objFilename As FileStream = New FileStream(strFileName, FileMode.Open, FileAccess.Read, FileShare.Read) Dim objFileRead As StreamReader = New StreamReader(objFilename) 'Dim lLineCount As Long 'Dim sNextLine As String '====================================================================================== '======================================================================================== Private Sub btStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btStart.Click Try If objFileRead.ReadLine = Nothing Then MsgBox("No Accounts Available to show!", MsgBoxStyle.Information, MsgBoxStyle.DefaultButton2 = MsgBoxStyle.OkOnly) Return Else Do While (objFileRead.Peek() > -1) Loop lblAccounts.Text = objFileRead.ReadLine() 'objFileRead.Close() 'objFilename.Close() End If Catch ex As Exception MessageBox.Show(ex.Message) Finally 'objFileRead.Close() 'objFilename.Close() End Try End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class

    Read the article

  • query sql database for specific value in vb.net

    - by user2952298
    I am trying to convert VBA code to vb.net, im having trouble trying to search the database for a specific value around an if statement. any suggestions would be greatly appriciated. thedatabase is called confirmation, type is the column and email is the value im looking for. could datasets work? Function SendEmails() As Boolean Dim objOutlook As Outlook.Application Dim objOutlookMsg As Outlook.MailItem Dim objOutlookRecip As Outlook.Recipient Dim objOutlookAttach As Outlook.Attachment Dim intResponse As Integer Dim confirmation As New ADODB.Recordset Dim details As New ADODB.Recordset On Error GoTo Err_Execute Dim MyConnObj As New ADODB.Connection Dim cn As New ADODB.Connection() MyConnObj.Open( _ "Provider = sqloledb;" & _ "Server=myserver;" & _ "Database=Email_Text;" & _ "User Id=bla;" & _ "Password=bla;") confirmation.Open("Confirmation_list", MyConnObj) details.Open("MessagesToSend", MyConnObj) If details.EOF = False Then confirmation.MoveFirst() Do While Not confirmation.EOF If confirmation![Type] = "Email" Then ' Create the Outlook session. objOutlook = CreateObject("Outlook.Application") ' Create the message. End IF

    Read the article

  • How to take a NSString such as, "0+1+2", get the sum of those and create new string. Obj-C

    - by Ace Legend
    Alright. My app has a text field and next to it are two buttons (Plus button and Equals button). When you press the "Plus" button, it takes the text inside of the textField and adds a "+" to it. Code below: - (IBAction)plusButtonPressed:(id)sender { NSString *plusString = @"+"; NSString *inputString = carbsField.text; NSString *outputString = [NSString stringWithFormat:@"%@%@",inputString,plusString]; NSLog(@"%@",outputString); [carbsField setText:outputString]; } I will eventually make that more intelligent so that I can't put two pluses or whatever. Anyway, then I want the equal button to take whatever is in the textField, which should look something like: "23+54+2.2" and get the sum of those values. I believe I know how to take an Integer and make it a String, but I want to verify it: int *value = 56; NSString *string = @"%d",value; Well, if anyone can show me how to do this, I would be very appreciative. Thanks. EDIT At the moment, I have not tried anything. This is because I do not know where to start. I have an idea of what to do, but I do not know how to execute it. I believe I need to get all characters before a "+" convert them into int and then get the sum of some array of those values.

    Read the article

  • Spinner setonitemselectedlistener is not called

    - by Gabrielle
    I have a strange problem. I need to do something when an item from spinner is selected. Here is my code : language = (Spinner) findViewById(R.id.current_language_text); ArrayAdapter adapter = new ArrayAdapter(this, com.Orange.R.layout.my_spinner_textview, languages); adapter.setDropDownViewResource(com.Orange.R.layout.multiline_spinner_dropdown_item); language.setAdapter(adapter); language.setSelection(Integer.valueOf(language_id) - 1); language.setOnItemSelectedListener(new OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) { System.out.println("position "+position); Toast.makeText(Settings.this, "Hello Toast",Toast.LENGTH_SHORT).show(); } @Override public void onNothingSelected(AdapterView<?> parentView) { // your code here } }); The problem is that onItemSelectedListener is not called. I put System.out.println in onItemSelected() but I don't get it in LogCat. I tried with Toast, and I get the same, it doesn't appear. Every time I select an item from spinner, in LogCat I get this warning : Window already focused, ignoring focus gain of: com.android.internal.view.IInputMethodClient$Stub$Proxy@2b1dabd0 Any idea why onItemSelectedListener is not called ?

    Read the article

  • C struct written in file, open with Java

    - by DaunnC
    For example in C I have structure: typedef struct { int number; double x1; double y1; double x2; double y2; double x3; double y3; } CTRstruct;` Then I write it to file fwrite(&tr, 1, sizeof(tr), fp); (tr - its CTRstruct var, fp - File pointer); Then I need to read it with Java! I really don't know how to read struct from file... I tried to read it with ObjectInputStream(), last idea is to read with RandomAccessFile() but I also don't know how to... (readLong(), readDouble() also doesn't work, it works ofcource but doesn't read correct data). So, any idea how to read C struct from binary file with Java? If it's interesting, my version to read integer (but it's ugly, & I don't know what to do with double): public class MyDataInputStream extends DataInputStream{ public MyDataInputStream(InputStream AIs) { super(AIs); } public int readInt1() throws IOException{ int ch1 = in.read(); int ch2 = in.read(); int ch3 = in.read(); int ch4 = in.read(); if ((ch1 | ch2 | ch3 | ch4) < 0) throw new EOFException(); return ((ch4 << 24) + (ch3 << 16) + (ch2 << 8) + (ch1 << 0)); } with double we can deal the same way (like with int or with long (8bytes) & then convert to double with native func).

    Read the article

  • Convert VBA to VBS

    - by dnLL
    I have a little VBA script with some functions that I would like to convert to a single VBS file. Here is an example of what I got: Private Declare Function GetPrivateProfileString Lib "kernel32" Alias "GetPrivateProfileStringA" (ByVal lpApplicationName As String, ByVal lpKeyName As Any, ByVal lpDefault As String, ByVal lpReturnedString As String, ByVal nSize As Long, ByVal lpFileName As String) As Long Private Function ReadIniFileString(ByVal Sect As String, ByVal Keyname As String) As String Dim Worked As Long Dim RetStr As String * 128 Dim StrSize As Long Dim iNoOfCharInIni As Integer Dim sIniString, sProfileString As String iNoOfCharInIni = 0 sIniString = "" If Sect = "" Or Keyname = "" Then MsgBox "Erreur lors de la lecture des paramètres dans " & IniFileName, vbExclamation, "INI" Access.Application.Quit Else sProfileString = "" RetStr = Space(128) StrSize = Len(RetStr) Worked = GetPrivateProfileString(Sect, Keyname, "", RetStr, StrSize, IniFileName) If Worked Then iNoOfCharInIni = Worked sIniString = Left$(RetStr, Worked) End If End If ReadIniFileString = sIniString End Function And then, I need to use this function to put some values in strings. VBS doesn't seem to like any of my var declaration ((Dim) MyVar As MyType). If I'm able to adapt that code to VBS, I should be able to do the rest of my functions too. How can I adapt/convert this to VBS? Thank you.

    Read the article

  • Why does this javascript code have an infinite loop?

    - by asdas
    optionElements is a 2d array. Each element has an array of length 2. These are an integer number and an element. I have a select list called linkbox, and i want to add all of the elements to the select list. The order I want them to go in is important, and is determined by the number each element has. It should be smallest to highest. So think of it like this: optionElements is: [ [5, <option>], [3, <option], [4, <option], [1, <option], [2, <option]] and it would add them to link box in order of those numbers. BUT that is not what happens. It is an infinite loop after the first time. I added the x constraint just to stop it from freezing my browser but you can ignore it. var b; var smallest; var samllestIndex; var x = 0; while(optionElements.length > 0 && ++x < 100) { smallestIndex = 0; smallest = optionElements[0][0]; b = 0; while( ++b < optionElements.length) { if(optionElements[b][0] > smallest) { smallestIndex = b; smallest = optionElements[b][0]; } } linkbox.appendChild(optionElements[smallestIndex][1]); optionElements.unshift(optionElements[smallestIndex]); } can someone point out to me where my problem is?

    Read the article

  • Reading lines of data from text files using java

    - by razshan
    I have a text file with x amount of lines. each line holds a integer number. When the user clicks a button, an action is performed via actionlistener where it should list all the values as displayed on the text file. However, right now I have linenum set to 10 implying I already told the code that just work with 10 lines of the text file. So, if my text file has only 3 rows/lines of data...it will list those lines and for rest of the other 7 lines, it will spit out "null". I recall there is a way to use ellipsis to let the program know that you don't know the exact value but at the end it calculates it based on the given information. Where my given information will the number of lines with numbers(data). Below is part of the code. private class thehandler implements ActionListener{ public void actionPerformed(ActionEvent event){ BufferedReader inputFile=null; try { FileReader freader =new FileReader("Data.txt"); inputFile = new BufferedReader(freader); String MAP = ""; int linenum=10; while(linenum > 0) { linenum=linenum-1; MAP = inputFile.readLine();//read the next line until the specfic line is found System.out.println(MAP); } } catch( Exception y ) { y.printStackTrace(); } }}

    Read the article

  • Algorithm to pick values from set to match target value?

    - by CSharperWithJava
    I have a fixed array of constant integer values about 300 items long (Set A). The goal of the algorithm is to pick two numbers (X and Y) from this array that fit several criteria based on input R. Formal requirement: Pick values X and Y from set A such that the expression X*Y/(X+Y) is as close as possible to R. That's all there is to it. I need a simple algorithm that will do that. Additional info: The Set A can be ordered or stored in any way, it will be hard coded eventually. Also, with a little bit of math, it can be shown that the best Y for a given X is the closest value in Set A to the expression X*R/(X-R). Also, X and Y will always be greater than R From this, I get a simple iterative algorithm that works ok: int minX = 100000000; int minY = 100000000; foreach X in A if(X<=R) continue; else Y=X*R/(X-R) Y=FindNearestIn(A, Y);//do search to find closest useable Y value in A if( X*Y/(X+Y) < minX*minY/(minX+minY) ) then minX = X; minY = Y; end end end I'm looking for a slightly more elegant approach than this brute force method. Suggestions?

    Read the article

  • JavaScript: why `null == 0` is false?

    - by lemonedo
    I had to write a routine that increments the value of a variable by 1 if it is a number, or assigns 0 to the variable if it is not a number. The variable can be incremented by the expression, or be assigned null. No other write access to the variable is allowed. So, the variable can be in three states: it is 0, a positive integer, or null. My first implementation was: v >= 0 ? v += 1 : v = 0 (Yes, I admit that v === null ? v = 0 : v += 1 is the exact solution, but I wanted to be concise then.) It failed since null >= 0 is true. I was confused, since if a value is not a number, an numeric expression involving it must be false always. Then I found that null is like 0, since null + 1 == 1, 1 / null == Infinity, Math.pow(2.718281828, null) == 1, ... Strangely enough, however, null == 0 is evaluated to false. I guess null is the only value that makes the following expression false: (v == 0) === (v >= 0 && v <= 0) So why null is so special in JavaScript?

    Read the article

  • UnauthorizedAccessException when running desktop application from shared folder

    - by Atara
    I created a desktop application using VS 2008. When I run it locally, all works well. I shared my output folder (WITHOUT allowing network users to change my files) and ran my exe from another Vista computer on our intranet. When running the shared exe, I receive "System.UnauthorizedAccessException" when trying to read a file. How can I give permission to allow reading the file? Should I change the code? Should I grant permission to the application\folder on the Vista computer? how? Notes: I do not use ClickOnce. the application should be distributed using xcopy. My application target framework is ".Net Framework 2.0" On the Vista computer, "controlPanel | UninstallOrChangePrograms" it says it has "Microsoft .Net Framework 3.5 SP1" I also tried to map the folder drive, but got the same errors, only now the fileName is "T:\my.ocx" ' ---------------------------------------------------------------------- ' my code: Dim src As String = mcGlobals.cmcFiles.mcGetFileNameOcx() Dim ioStream As New System.IO.FileStream(src, IO.FileMode.Open) ' ---------------------------------------------------------------------- Public Shared Function mcGetFileNameOcx() As String ' ---------------------------------------------------------------------- Dim dirName As String = Application.StartupPath & "\" Dim sFiles() As String = System.IO.Directory.GetFiles(dirName, "*.ocx") Dim i As Integer For i = 0 To UBound(sFiles) Debug.WriteLine(System.IO.Path.GetFullPath(sFiles(i))) ' if found any - return the first: Return System.IO.Path.GetFullPath(sFiles(i)) Next Return "" End Function ' ---------------------------------------------------------------------- ' The Exception I receive: System.UnauthorizedAccessException: Access to the path '\\computerName\sharedFolderName\my.ocx' is denied. at System.IO._Error(Int32 errorCode, String maybeFullPath) at System.IO.FileStream.Init(...) at System.IO.FileStream..ctor(...) at System.IO.FileStream..ctor(String path, FileMode mode) ' ----------------------------------------------------------------------

    Read the article

  • How to implement a grapher in C#

    - by iansinke
    So I'm writing a graphing calculator. So far I have a semi-functional grapher, however, I'm having a hard time getting a good balance between accurate graphs and smooth looking curves. The current implementation (semi-pseudo-code) looks something like this: for (float i = GraphXMin; i <= GraphXMax; i++) { PointF P = new PointF(i, EvaluateFunction(Function, i) ListOfPoints.Add(P) } Graphics.DrawCurve(ListOfPoints) The problem with this is since it only adds a point at every integer value, graphs end up distorted when their turning points don't fall on integers (e.g. sin(x)^2). I tried incrementing i by something smaller (like 0.1), which works, but the graph looks very rough. I am using C# and GDI+. I have SmoothingMethod set to AntiAlias, so that's not the problem, as you can see from the first graph. Is there some sort of issue with drawing curves with a lot of points? Should the points perhaps be positioned exactly on pixels? I'm sure some of you have worked on something very similar before, so any suggestions? While you're at it, do you have any suggestions for graphing functions with asymptotes? e.g. 1/x^2 P.S. I'm not looking for a library that does all this - I want to write it myself.

    Read the article

  • How to alter Postgres table data based on its contents?

    - by williamjones
    This is probably a super simple question, but I'm struggling to come up with the right keywords to find it on Google. I have a Postgres table that has among its contents a column of type text named content_type. That stores what type of entry is stored in that row. There are only about 5 different types, and I decided I want to change one of them to display as something else in my application (I had been directly displaying these). It struck me that it's funny that my view is being dictated by my database model, and I decided I would convert the types being stored in my database as strings into integers, and enumerate the possible types in my application with constants that convert them into their display names. That way, if I ever got the urge to change any category names again, I could just change it with one alteration of a constant. I also have the hunch that storing integers might be somewhat more efficient than storing text in the database. First, a quick threshold question of, is this a good idea? Any feedback or anything I missed? Second, and my main question, what's the Postgres command I could enter to make an alteration like this? I'm thinking I could start by renaming the old content_type column to old_content_type and then creating a new integer column content_type. However, what command would look at a row's old_content_type and fill in the new content_type column based off of that?

    Read the article

  • Python: why can't descriptors be instance variables?

    - by Continuation
    Say I define this descriptor: class MyDescriptor(object): def __get__(self, instance, owner): return self._value def __set__(self, instance, value): self._value = value def __delete__(self, instance): del(self._value) And I use it in this: class MyClass1(object): value = MyDescriptor() >>> m1 = MyClass1() >>> m1.value = 1 >>> m2 = MyClass1() >>> m2.value = 2 >>> m1.value 2 So value is a class attribute and is shared by all instances. Now if I define this: class MyClass2(object) value = 1 >>> y1 = MyClass2() >>> y1.value=1 >>> y2 = MyClass2() >>> y2.value=2 >>> y1.value 1 In this case value is an instance attribute and is not shared by the instances. Why is it that when value is a descriptor it can only be a class attribute, but when value is a simple integer it becomes an instance attribute?

    Read the article

  • Thread mutex behaviour

    - by Alberteddu
    Hi there, I'm learning C. I'm writing an application with multiple threads; I know that when a variable is shared between two or more threads, it is better to lock/unlock using a mutex to avoid deadlock and inconsistency of variables. This is very clear when I want to change or view one variable. int i = 0; /** Global */ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; /** Thread 1. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); /** Thread 2. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); This is correct, I think. The variable i, at the end of the executions, contains the integer 2. Anyway, there are some situations in which I don't know exactly where to put the two function calls. For example, suppose you have a function obtain(), which returns a global variable. I need to call that function from within the two threads. I have also two other threads that call the function set(), defined with a few arguments; this function will set the same global variable. The two functions are necessary when you need to do something before getting/setting the var. /** (0) */ /** Thread 1, or 2, or 3... */ if(obtain() == something) { if(obtain() == somethingElse) { // Do this, sometimes obtain() and sometimes set(random number) (1) } else { // Do that, just obtain(). (2) } } else { // Do this and do that (3) // If # of thread * 3 > 10, then set(3*10) For example. (4) } /** (5) */ Where I have to lock, and where I have to unlock? The situation can be, I think, even more complex. I will appreciate an exhaustive answer. Thank you in advance. —Alberto

    Read the article

  • switch statemt functioning improperly and giving error when i put break;

    - by nav
    The following is the code i used in a program - over here the month variable is an integer switch(month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: return 31; break; case 2: return 28; break; case 4: case 6: case 9: case 11: return 30; break; default: System.out.println("Invalid month."); return 0; } surprisingly, when i use the above switch construct.. it gives an error saying.. code unreachable for statements after each break statement Then i removed all the break statements, and the new code looks like this --- switch(month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: return 31; case 2: return 28; case 4: case 6: case 9: case 11: return 30; default: System.out.println("Invalid month."); return 0; } Now.. after removing the break statements .. the code worked perfectly well.. My question is... in the switch construct.. it is mandatory to use break.. or else the control flow continued.. and all the conditions are tested and executed!! right??? So why in the world is the previous ** syntactically Right** version giving an error.. and the modified syntactically incorrect version running perfectly well.. Any explanation.. anyone!!

    Read the article

< Previous Page | 218 219 220 221 222 223 224 225 226 227 228 229  | Next Page >