Search Results

Search found 6442 results on 258 pages for 'beginner programmer'.

Page 68/258 | < Previous Page | 64 65 66 67 68 69 70 71 72 73 74 75  | Next Page >

  • Python f.write() at beginning of file?

    - by kristus
    I'm doing it like this now, but i want it to write at the beginning of the file instead. f = open('out.txt', 'a') # or 'w'? f.write("string 1") f.write("string 2") f.write("string 3") f.close() so that the contenst of out.txt will be: string 3 string 2 string 1 and not (like this code does): string 1 string 2 string 3

    Read the article

  • AWK: how to reuse a result NR-times without removing END?

    - by HH
    How can I get all differences, not just one? I want to use the calculated result for each item in the third column. The dilemma is that if I remove END I can print $3 but cannot have ave. If I leave END I have ave but not all differences. awk '{sum+=$3} END {ave=sum/NR} END {print $3-ave}' coriolis_data -0.00964 // I want to see the rest differences, how? coriolis_data .105 0.005 0.9766 0.0001 0.595 0.005 .095 0.005 0.9963 0.0001 0.595 0.005 .115 0.005 0.9687 0.0001 0.595 0.005 .105 0.005 0.9693 0.0001 0.595 0.005 .095 0.005 0.9798 0.0001 0.595 0.005 .105 0.005 0.9798 0.0001 0.595 0.005 .095 0.005 0.9711 0.0001 0.595 0.005 .110 0.005 0.9640 0.0001 0.595 0.005 .105 0.005 0.9704 0.0001 0.595 0.005 .090 0.005 0.9644 0.0001 0.595 0.005

    Read the article

  • An old flaw in X Window System. How does it work?

    - by Legend
    I was going through an article today when it mentioned the following: "We've found many errors over the years. One of the absolute best was the following in the X Window System: if(getuid() != 0 && geteuid == 0) { ErrorF("Only root"); exit(1); } It allowed any local user to get root access. (The tautological check geteuid == 0 was intended to be geteuid() == 0. In its current form, it compress the address of geteuid to 0; given that the function exists, its address is never 0)." The article explained what was wrong with the code but I would like to know what it means to say that "It allowed any local user to get root access". I am not an expert in C but can someone give me an exact context in which this exploit would work? Specifically, what I mean is, lets say I am the local user, how would I get root access if we assume this code to be present somewhere?

    Read the article

  • C Array of string

    - by Meko
    HI. This is maybe simple question but I want to create two dimensional array and add it string like in java string str = "text" ; string [][] array = new [][] string ; array[i][j] = str ; But in C there is no string .I tried like this but here strcpy() gives error.It returns to assembly code. I am trying to read line by line from text and split line by space and add them to structure.But first I think that I must add each line and row in array and then making iteration and adding to structures fields. static const char filename[] = "student.txt"; FILE *file = fopen ( filename, "r" ); char line [ 128 ]; /* or other suitable maximum line size */ char delims [ ]=" "; char *result =NULL; char list[15]; char arra[128][128]; int i=0; int j=0; struct { char gruppa[10]; char familiya[20]; int uchaste; struct { int firsth; int second; int third; int fourht; int fifth; } exam; }student; for(i=0; i<128; i++) for(j=0; j<128; j++) arra[i][j] = '\0'; for(i=0; i<15; i++) list[i] = '\0'; if ( file != NULL ) { while ( fgets ( line, sizeof line, file ) != NULL ) { result = strtok(line,delims); while (result !=NULL) { strcpy(list,("%s",result)); strcpy(arra[i][j],list); // Here it gives errror j++; result = strtok(NULL,delims); } j=0; i++; } fclose ( file ); } else { perror ( filename ); } getchar(); return 0; }

    Read the article

  • python: equivalent to Javascript "||" to override non-truthful value

    - by Jason S
    In Javascript I can do this: function A(x) { return x || 3; } This returns 3 if x is a "non-truthful" value like 0, null, false, and it returns x otherwise. This is useful for empty arguments, e.g. I can do A() and it will evaluate as 3. Does Python have an equivalent? I guess I could make one out of the ternary operator a if b else c but was wondering what people use for this.

    Read the article

  • jQuery: What does (function($) {})(jQuery); mean?

    - by Legend
    I am just starting out with writing jQuery plugins. I wrote three small plugins but I have been simply copying the line into all my plugins without actually knowing what it means. Can someone tell me a little more about these? What does this do? (I know it extends jQuery somehow but is there anything else interesting to know about this) (function($) { })(jQuery); What is the difference between the following two ways of writing a plugin: Type 1: (function($) { $.fn.jPluginName = { }, $.fn.jPluginName.defaults = { } })(jQuery); Type 2: (function($) { $.jPluginName = { } })(jQuery); I could be way off here and maybe both mean the same thing. In some cases, this doesn't seem to be working in a plugin that I was writing using Type 1. Any idea why? But in either case, I would appreciate any explanation.

    Read the article

  • MySQL::Eliminating redundant elements from a table?

    - by Legend
    I have a table like this: +-------+---------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+---------+------+-----+---------+-------+ | v1 | int(11) | YES | MUL | NULL | | | v2 | int(11) | YES | MUL | NULL | | +-------+---------+------+-----+---------+-------+ There is a tremendous amount of duplication in this table. For instance, elements like the following: +------+------+ | v1 | v2 | +------+------+ | 1 | 2 | | 1 | 3 | | 1 | 4 | | 1 | 5 | | 1 | 6 | | 1 | 7 | | 1 | 8 | | 1 | 9 | | 2 | 1 | | 4 | 1 | | 5 | 1 | | 6 | 1 | | 7 | 1 | | 8 | 1 | | 9 | 1 | +------+------+ The table is large with 1540000 entries. To remove the redundant entries (i.e. to get a table having only (1,9) and no (9,1) entries), I was thinking of doing it with a subquery but is there a better way of doing this?

    Read the article

  • When I overload the assignment operator for my simple class array, I get the wrong answer I espect

    - by user299648
    //output is "01234 00000" but the output should be or what I want it to be is // "01234 01234" because of the assignment overloaded operator #include <iostream> using namespace std; class IntArray { public: IntArray() : size(10), used(0) { a= new int[10]; } IntArray(int s) : size(s), used(0) { a= new int[s]; } int& operator[]( int index ); IntArray& operator =( const IntArray& rightside ); ~IntArray() { delete [] a; } private: int *a; int size; int used;//for array position }; int main() { IntArray copy; if( 2>1) { IntArray arr(5); for( int k=0; k<5; k++) arr[k]=k; copy = arr; for( int j=0; j<5; j++) cout<<arr[j]; } cout<<" "; for( int j=0; j<5; j++) cout<<copy[j]; return 0; } int& IntArray::operator[]( int index ) { if( index >= size ) cout<<"ilegal index in IntArray"<<endl; return a[index]; } IntArray& IntArray::operator =( const IntArray& rightside ) { if( size != rightside.size )//also checks if on both side same object { delete [] a; a= new int[rightside.size]; } size=rightside.size; used=rightside.used; for( int i = 0; i < used; i++ ) a[i]=rightside.a[i]; return *this; }

    Read the article

  • How do I set up my @product=Product.find(params[:id]) to have a product_url?

    - by montooner
    Trying to recreate { script/generate scaffold }, and I've gotten thru a number of Rails basics. I suspect that I need to configure default product url somewhere. But where do I do this? Setup: Have: def edit { @product=Product.find(params[:id]) } Have edit.html.erb, with an edit form posting to action = :create Have def create { ... }, with the code redirect_to(@product, ...) Getting error: undefined method `product_url' for #< ProductsController:0x56102b0 My def update: def update @product = Product.find(params[:id]) respond_to do |format| if @product.update_attributes(params[:product]) format.html { redirect_to(@product, :notice => 'Product was successfully updated.') } format.xml { head :ok } else format.html { render :action => "edit" } format.xml { render :xml => @product.errors, :status => :unprocessable_entity } end end end

    Read the article

  • How to make if-elif-else statement in python more space-saving?

    - by Neverland
    I have a lot of if-elif-else statements in my code if message == '0' or message == '3' or message == '5' or message == '7': ... elif message == '1' or message == '2' or message == '4' or message == '6' or message == '8': ... else: ... Is it possible to format this in a more space-saving way? I tried it this way: if message == '0' or '3' or '5' or '7': ... elif message == '1' or '2' or '4' or '6' or '8': ... else: ... But without success.

    Read the article

  • Unix: cannot add "\\ \n" even with escaping to the end of line

    - by HH
    I try to convert clean columnwise data to tables in tex. I am unable to have "\ \n" at each end of line. Please, see the command at the end. Data $ echo `. ./bin/addTableTexTags.sh < .data_3` 10.31 & 8.50 & 7.40 10.34 & 8.53 & 7.81 8.22 & 8.62 & 7.78 10.16 & 8.53 & 7.44 10.41 & 8.38 & 7.63 10.38 & 8.57 & 8.03 10.13 & 8.66 & 7.41 8.50 & 8.60 & 7.15 10.41 & 8.63 & 7.21 8.53 & 8.53 & 7.12 $ cat .data_3 10.31 8.50 7.40 10.34 8.53 7.81 8.22 8.62 7.78 10.16 8.53 7.44 10.41 8.38 7.63 10.38 8.57 8.03 10.13 8.66 7.41 8.50 8.60 7.15 10.41 8.63 7.21 8.53 8.53 7.12 addTableTexTags.sh #!/bin/bash sed -e "s@[[:space:]]@\t\&\t@g" -e "s@[[:space:]]*&*[[:space:]]*\$@\t \\ \\\\n@g" // Tried Escaping "\\" with "/" here and there // but cannot get a line ending with "\\ \n".

    Read the article

  • Permutations in python 2.5.2

    - by flpgdt
    Hi, I have a list of numbers for input, e.g. 671.00 1,636.00 436.00 9,224.00 and I want to generate all possible sums with a way to id it for output, e.g.: 671.00 + 1,636.00 = 2,307.00 671.00 + 436.00 = 1,107.00 671.00 + 9,224.00 = 9,224.00 671.00 + 1,636.00 + 436.00 = 2,743.00 ... and I would like to do it in Python My current constrains are: a) I'm just learning python now (that's part of the idea) b) I will have to use Python 2.5.2 (no intertools) I think I have found a piece of code that may help: def all_perms(str): if len(str) <=1: yield str else: for perm in all_perms(str[1:]): for i in range(len(perm)+1): #nb str[0:1] works in both string and list contexts yield perm[:i] + str[0:1] + perm[i:] ( from these guys ) But I'm not sure how to use it in my propose. Could someone trow some tips and pieces of code of help? cheers, f.

    Read the article

  • [solved] What's wrong with this jQuery example?

    - by Sven Larson
    The following jQuery example should put some text into the div, but it doesn't. I tried Firefox, Google Chrome and Internet Explorer. <html> <head> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js" language="javascript"></script> <script language="javascript"> $(window).load(function() { $('adiv').html('<p>hello world</p>'); alert('done'); }); </script> </head> <body> <div id="adiv"> </div> </body> </html> Sorry, this might be stupid, but I'm stuck.

    Read the article

  • Clicking Elements in Android Doesn't Display the Correct Values

    - by Devin
    I apologize if this code looks a bit like a mess (considering the length); I figured I'd just include everything that goes on in my program at the moment. I'm attempting to create a fairly simple Tic Tac Toe app for Android. I've set up my UI nicely so far so that there are a "grid" of TextViews. As a sort of "debug" right now, I have it so that when one clicks on a TextView, it should display the value of buttonId in a message box. Right now, it displays the correct assigned value for the first element I click, but no matter what I click afterwards, it always just displays the first value buttonID had. I attempted to debug it but couldn't exactly find a point where it would pull the old value (to the best of my knowledge, it reassigned the value). There's a good possibility I'm missing something small, because this is my first Android project (of any note). Can someone help get different values of buttonId to appear or point out the error in my logic? The code: package com.TicTacToe.app; import com.TicTacToe.app.R; //Other import statements public class TicTacToe extends Activity { public String player = "X"; public int ALERT_ID; public int buttonId; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //Sets up instances of UI elements final TextView playerText = (TextView)findViewById(R.id.CurrentPlayerDisp); final Button button = (Button) findViewById(R.id.SetPlayer); final TextView location1 = (TextView)findViewById(R.id.location1); final TextView location2 = (TextView)findViewById(R.id.location2); final TextView location3 = (TextView)findViewById(R.id.location3); final TextView location4 = (TextView)findViewById(R.id.location4); final TextView location5 = (TextView)findViewById(R.id.location5); final TextView location6 = (TextView)findViewById(R.id.location6); final TextView location7 = (TextView)findViewById(R.id.location7); final TextView location8 = (TextView)findViewById(R.id.location8); final TextView location9 = (TextView)findViewById(R.id.location9); playerText.setText(player); //Handlers for events button.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // Perform action on click if (player.equals("X")){ player = "O"; playerText.setText(player); } else if(player.equals("O")){ player = "X"; playerText.setText(player); } //Sets up the dialog buttonId = 0; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location1.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 1; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location2.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 2; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location3.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 3; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location4.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 4; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location5.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 5; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location6.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 6; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location7.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 7; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location8.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 8; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); location9.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Sets up the dialog buttonId = 9; ALERT_ID = 0; onCreateDialog(ALERT_ID); showDialog(ALERT_ID); } }); } protected Dialog onCreateDialog(int id){ String msgString = "You are on spot " + buttonId; AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setMessage(msgString) .setCancelable(false) .setNeutralButton("Ok", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { dialog.cancel(); } }); AlertDialog alert = builder.create(); return alert; } }

    Read the article

  • GoTo statements and alternatives in VB.NET

    - by qais
    I've posted a code snippet on another forum asking for help and people pointed out to me that using GoTo statements is very bad programming practice. I'm wondering: why is it bad? What alternatives to GoTo are there to use in VB.NET that would be considered generally more of a better practice? Consider this snippet below where the user has to input their date of birth. If the month/date/year are invalid or unrealistic(using if statements checking the integer inputs size, if there's a better way to do this, I'd appreciate if you could tell me that also :D) How would I be able to loop back to ask the user again? retryday: Console.WriteLine("Please enter the day you were born : ") day = Console.ReadLine If day > 31 Or day < 1 Then Console.WriteLine("Please enter a valid day") GoTo retryday End If

    Read the article

  • Declaring an integer Range with step != 1 in Ruby

    - by Dan Tao
    Hey guys, I'm completely new to Ruby, so be gentle. Say I want to iterate over the range of even numbers from 2 to 100; how would I do that? Obviously I could do: (2..100).each do |x| if x % 2 == 0 # my code end end But, obviously (again), that would be pretty stupid. I know I could do something like: i = 2 while i <= 100 # my code i += 2 end I believe I could also write my own custom class that provides its own each method (?). I am almost sure that would be overkill, though. I'm interested in two things: Is it possible to do this with some variation of the standard Range syntax (i.e., (x..y).each)? Either way, what would be the most idiomatic "Ruby way" of accomplishing this (using a Range or otherwise)? Like I said, I'm new to the language; so any guidance you can offer on how to do things in a more typical Ruby style would be much appreciated.

    Read the article

  • Windows server issue with a product

    - by peter
    Can you tell me the meaning of this statement.I am using windows 2008 server OS Log Problem must be changed so that it elevates privileges for a user executing the Problem. its done by creating a manifest that indicates that Problem needs Administrator privileges.

    Read the article

  • Is it a good idea for me to learn Python before C or some other Compiler language?

    - by Dream Lane
    Right now I am going through MIT's introduction to Computer Science course via OpenCourseWare. As a part of this course I am learning the Python Language. I've read a lot of things about the benefits of learning C. Before I dig any deeper into Python I wonder if I will be hindered or helped by learning Python first. Do you think that I will develop any bad habits or anything like that from Python?

    Read the article

  • Drupal - Generating forms from the database.

    - by YsoL8
    Hello I'm trying to teach myself Drupal and I've found something I can't find any tutorials for. I am trying to generate a form, with a dynamic number of text fields, to populate and edit the contents of my custom table. In regular PHP I would achieve this with: $count = '0'; while ($row = mysql_fetch_array ($result) { echo "<input type='text' name='title_row".$count."' value='".$row['title']."'>" $count = $count +1; } Can someone point me to something that'll show me how to do that in Drupal (and processing the submited data)? Thanks

    Read the article

< Previous Page | 64 65 66 67 68 69 70 71 72 73 74 75  | Next Page >