Search Results

Search found 10295 results on 412 pages for 'rails beginner'.

Page 207/412 | < Previous Page | 203 204 205 206 207 208 209 210 211 212 213 214  | Next Page >

  • Why C++ is (one of) the best language to learn at first [closed]

    - by AlexV
    C++ is one of the most used programming language in the world since like 25+ years. My first job as programmer was in C++ and I coded in C++ everyday for nearly 4 years. Now I do mostly PHP, but I will forever cherish this C++ background. C++ has helped me understand many "under the hood" features/behaviors/restrictions of many other (and different) programming languages like PHP and Delphi. I'm a full time programmer for 6+ years now and since I have a quite varied programming background I often get questions by "newbies" as where to start to become a "good" programmer. I think C++ is one of the best language to start with because it gives you a real usefull experience that will last and will teach you how things work under the hood. It's not the easier one to learn for a newbie, but in my opinion it's the one who will reward the most in long term. I would like to know your opinion on this matter to add to my arguments when I guide "newbies". After this introduction, here's my question : Why C++ is for you (one of) the best language to learn at first. Since it's subjective, I've marked this question as community wiki.

    Read the article

  • An array problem in C++

    - by manugupt1
    To access the array indice at the xth position we can use some sort of illustration as shown below #include<iostream> using namespace std; int main(){ float i[20]; for(int j=0;j<=20;j++) i[j]=0; } However the following piece of code does not work #include<iostream> using namespace std; float oldrand[55]; int jrand; void advance_random(){ int j1; float new_random; for(j1=0;j1<=23;j1++){ int temp = j1+30; new_random = (oldrand[j1]) - (oldrand[temp]); if(new_random <0.0) new_random = new_random+1; oldrand[j1] = new_random; } for(j1=24;j1<=54;j1++){ new_random[j1] = oldrand[j1] - oldrand[j1-23]; if(new_random[j1]<0.0) new_random[j1] = new_random + 1; oldrand[j1]=new_random; } } I recieve the following error ga.cpp:20: error: invalid types ‘float[int]’ for array subscript ga.cpp:21: error: invalid types ‘float[int]’ for array subscript ga.cpp:22: error: invalid types ‘float[int]’ for array subscript I am not able to find a mistake in my code please help me

    Read the article

  • Trying to reinvent the wheel of StackOverflow to have a good learning experience. Need some suggesti

    - by Legend
    I want to learn and am not able to do it unless I have a real "mission" to complete. SO is my favorite and I can't imagine a better experience than actually recreating it but not in ASP. I'd like to use PHP+MySQL+jQuery. So far, I have been a self-taught programmer but I would like to master one paradigm that forces you to adhere to the standards. For instance, recently, jQuery forced me to use some "rules". The plugins were supposed to be written in a particular way and that's it. When I started off, everything seemed like Greek and Latin but when I finished a very small plugin, I felt really happy because it forced me to program in a certain way. I am looking for something like this only in a larger project. I've heard a lot about MVC and all but I am confused about the various frameworks out there. Zend seems awesome but looks heavy at the same time and also requires you to have a lot more control over the web-server whereas CakePHP is a good and a fast framework that needs only little control. Do I use one of these or just write my own MVC? I have the following goals: Goals: Site should be fast - I know this depends on my coding skills but I will learn on my way. The framework itself should not slow me down) Setting up the site should not require you to use command-line - This requirement is ok during development. But some frameworks like Symphony require you to initialize certain things through command-line Should support pluggable modules - For instance, if I want to be able to use the FCK editor, I should be able to organize things in a good way. Should be possible to extend - For instance, SO is mainly a Q&A site but I should be able to logically extend it into an Idea Management System (optional but I'm curious). This goes more into code re-usability I guess. I am comfortable with MySQL so I should be done with database design etc. with some serious effort. As for PHP, I can write code on my own but haven't really used any frameworks that much. jQuery, I started off recently and love it. I would be glad if someone can guide me during these initial steps. Precisely, when designing something like SO, I have the following questions: Do I use a framework? If yes, should it be MVC? If MVC, which one is a good and a scalable one? (I'd love something like jQuery that will not die anytime soon) How do I balance the functionality? The same logic can sometimes be made server centric or client centric. (more Ajax?). Is it a good idea to make a heavy javascript site considering the recent advances on client-side JS processing? Just in case anyone is wondering, I am not interested in commercializing any of this. I need a reason to learn something :)

    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

  • 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

  • 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

  • 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

  • List in a Python class shares the same object over 2 different instances?

    - by zfranciscus
    I created a class: class A: aList = [] now I have function that instantiate this class and add items into the aList. note: there are 2 items for item in items: a = A(); a.aList.append(item); I find that the first A and the second A object has the same number of items in their aList. I would expect that the first A object will have the first item in its list and the second A object will have the second item in its aList. Can anyone explain how this happens ? PS: I manage to solve this problem by moving the aList inside a constructor : def __init__(self): self.aList = []; but I am still curious about this behavior

    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

  • Java Graphics not displaying on successive function calls, why?

    - by primehunter326
    Hi, I'm making a visualization for a BST implementation (I posted another question about it the other day). I've created a GUI which displays the viewing area and buttons. I've added code to the BST implementation to recursively traverse the tree, the function takes in coordinates along with the Graphics object which are initially passed in by the main GUI class. My idea was that I'd just have this function re-draw the tree after every update (add, delete, etc...), drawing a rectangle over everything first to "refresh" the viewing area. This also means I could alter the BST implementation (i.e by adding a balance operation) and it wouldn't affect the visualization. The issue I'm having is that the draw function only works the first time it is called, after that it doesn't display anything. I guess I don't fully understand how the Graphics object works since it doesn't behave the way I'd expect it to when getting passed/called from different functions. I know the getGraphics function has something to do with it. Relevant code: private void draw(){ Graphics g = vPanel.getGraphics(); tree.drawTree(g,ORIGIN,ORIGIN); } vPanel is what I'm drawing on private void drawTree(Graphics g, BinaryNode<AnyType> n, int x, int y){ if( n != null ){ drawTree(g, n.left, x-10,y+10 ); if(n.selected){ g.setColor(Color.blue); } else{ g.setColor(Color.gray); } g.fillOval(x,y,20,20); g.setColor(Color.black); g.drawString(n.element.toString(),x,y); drawTree(g,n.right, x+10,y+10); } } It is passed the root node when it is called by the public function. Do I have to have: Graphics g = vPanel.getGraphics(); ...within the drawTree function? This doesn't make sense!! Thanks for your help.

    Read the article

  • Python - Removing duplicates from a string

    - by Daniel
    def remove_duplicates(strng): """ Returns a string which is the same as the argument except only the first occurrence of each letter is present. Upper and lower case letters are treated as different. Only duplicate letters are removed, other characters such as spaces or numbers are not changed. >>> remove_duplicates('apple') 'aple' >>> remove_duplicates('Mississippi') 'Misp' >>> remove_duplicates('The quick brown fox jumps over the lazy dog') 'The quick brown fx jmps v t lazy dg' >>> remove_duplicates('121 balloons 2 u') '121 balons 2 u' """ s = strng.split() return strng.replace(s[0],"") Writing a function to get rid of duplicate letters but so far have been playing around for an hour and can't get anything. Help would be appreciated, thanks.

    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

  • how to get the parent dir location using python..

    - by zjm1126
    this code is get the templates/blog1/page.html in b.py: path = os.path.join(os.path.dirname(__file__), os.path.join('templates', 'blog1/page.html')) but i want to get the parent dir location: a |---b.py |---templates |--------blog1 |-------page.html and how to get the a location thanks

    Read the article

  • How to provide global functionality in multi-user database app

    - by Mike B
    I have been building a multi-user database application (in C#/WPF 4.0) that manages tasks for all employees of a company. I now need to add some functionality such as sending an email reminder to someone when a critical task is due. How should this be done? Obviously I don’t want every instance of the program to be performing this function (Heh each user would get 10+ emails). Should I add the capability to the application as a "Mode" and then run a copy on the database server in this mode or would it be better to create a new app altogether to perform "Global" type tasks? Is there a better way?

    Read the article

  • Execute a method less times possible - PHP

    - by serhio
    I have a site in multiple languages. I have a method that returns me the today currencies in a array. I display that currencies in a table then. // --- en/index.php <?php include_once "../exchangeRates.php"; $currencies = ReadExchangeRates(); // --- fr/index.php <?php include_once "../exchangeRates.php"; $currencies = ReadExchangeRates(); ... // somewhere in the page <td><?php echo $currencies["eur"]["today"]; ?></td> So, every time I load, en/ or fr/ or other language, I request the exchange rates from a external site. Can I optimize this behavior (reading once per day or session)? maybe to store a global variable and check the update date?

    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

  • How to get unique value in jquery?

    - by jquerier
    I am learning jquery. I have following chunk of code in a html file: <table width="100%"> <tr> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='1'><img src='images/1.gif'></a> </div> </td> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='2'><img src='images/2.gif'></a> </div> </td> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='3'><img src='images/3.gif'></a> </div> </td> </tr> What I want to do is, when I click any of the image, I can get the value, so that I can display the information. For example, I click the id=1, then I will display information on id1 in somewhere else. I tried this: $("a#get_this").click(function(){ var id = $('input[type=hidden]#id').val(); window.alert("You have chosen the id: " + id); }); It always return id: 1 to me.

    Read the article

  • SQL-wrappers (activerecord) to recommened for python?

    - by Horace Ho
    is there an activerecord (any similar SQL-wrapper) for python? which is good for: used in a server-side python script light-weight supports MySQL what I need to do: insert (filename, file size, file md5, the file itself) into (string, int, string, BLOB) columns if the same file (checksum + filename) does not exist in db thx

    Read the article

  • How to push further as a programmer?

    - by MaXX
    For the last, hmm, 6 months I've been reading into Programming in C, I got myself K&Rv2, BEEJ's socket guide, Expert C programming, Linux Systems Programming, the ISO/IEC 9899:1999 specification (real, and not draft). After receiving them from Amazon, I got Linux installed, and got to it. I'm done with K&R, about halfway through Expert C Programming, but still feel weak as a programmer, I'm sure it takes much more than 6 months of reading to become truly skilled, but my question is this: I've done all the exercises in K&Rv2 (in chapter 1) and some in other chapters, most of which are generally really boring. How do I lift my skills, and become truly great? I've invested money, time and a general lifestyle for something I truly desire, but I'm not sure how exactly to achieve it. Could someone explain to me, perhaps if I need to continuously code, what exactly I'm to code? I'm pretty sure, coding up hello world programs isn't going to teach me any more than I already know about anything. A friend of mine said "read" (with emphasis on read) a man page a day, but reading is all I do, I want to do, but I'm not sure what! I'm interested in security, but I'm not sure as a novice what to code that would be considered enough. Ah, I hope you don't delete this paste :) Thanks

    Read the article

  • Books on Debugging Techniques?

    - by zooropa
    Are there any books on debugging techniques? A friend of mine is learning to code and he asked me this question. I told him I don't know of any. Is it that you just have to go through the School of Hard Knocks to learn?

    Read the article

  • Psycopg2 doesn't like table names that start with a lower case letter

    - by Count Boxer
    I am running ActiveState's ActivePython 2.6.5.12 and PostgreSQL 9.0 Beta 1 under Windows XP. If I create a table with an upper case first letter (i.e. Books), psycopg2 returns the "Programming Error: relation "books" does not exist" error message when I run the select statement: execute("SELECT * FROM Books"). The same error is returned if I run: execute("SELECT * FROM books"). However, if I change the table to a lower case first name (i.e. books), then either of the above statements works. Are tables name supposed to have a lower case first name? Is this a setting or a feature or a bug? Am I missing something obvious?

    Read the article

  • Codeigniter: how should I restructure db schema?

    - by Kevin Brown
    I don't even know if that's the right term. May it be known that I'm a major novice! I have three tables: users, profiles, and survey. Each one has user_id as it's first field, (auto-increment for users), and they're all tied by a foreign key constraint, CASCADE on DELETE. Currently, for each user, let's say user_id 1, they have a corresponding db entry in the other tables. For profiles it lists all their information, and the survey table holds all their survey information. Now I must change things...darn scope creep. Users need the ability to have multiple survey results. I imagine that this would be similar to a comment table for a blog... My entire app runs around the idea that a single user is linked to a constraining profile and survey. How should I structure my db? How should I design my app's db so that a user can have multiple tests/profiles for the test? Please assist! Any advice, information and personal-knowledge is appreciated! Right now the only way I know how to accompany my client is to create a pseudo-user for each test (so unnecessary) and list them in a view table (called "your tests")-- these are obtained from the db by saying: where user_id=manager_id

    Read the article

< Previous Page | 203 204 205 206 207 208 209 210 211 212 213 214  | Next Page >