Search Results

Search found 31807 results on 1273 pages for 'app beginner'.

Page 79/1273 | < Previous Page | 75 76 77 78 79 80 81 82 83 84 85 86  | Next Page >

  • Java: how to access assignments in try-catch -loop?

    - by HH
    $ javac TestInit2.java TestInit2.java:13: variable unknown might not have been initialized System.out.println(unknown); ^ 1 error Code import java.util.*; import java.io.*; public class TestInit2 { public static void main(String[] args){ String unknown; try{ unknown="cannot see me, why?"; }catch(Exception e){ e.printStackTrace(); } System.out.println(unknown); } }

    Read the article

  • Can someone explain me implicit conversions in Scala?

    - by Oscar Reyes
    And more specifically how does the BigInt works for convert int to BigInt? In the source code it reads: ... implicit def int2bigInt(i: Int): BigInt = apply(i) ... How is this code invoked? I can understand how this other sample: "Date literals" works. In. val christmas = 24 Dec 2010 Defined by: implicit def dateLiterals(date: Int) = new { import java.util.Date def Dec(year: Int) = new Date(year, 11, date) } When int get's passed the message Dec with an int as parameter, the system looks for another method that can handle the request, in this case Dec(year:Int) Q1. Am I right in my understanding of Date literals? Q2. How does it apply to BigInt? Thanks

    Read the article

  • sort given set of colors in VIBGYOR order

    - by Vijay Selvaraj
    Hi, how do i order a given set of colors from the rainbow in VIBGYOR order. say i input the seven colors in the following order { red, blue, green, yellow, indigo, violet, orange} and i should print the output as {violet, indigo, blue, green, yellow, orange, red}, irrespective of the order i give the output should be as above. Can someone suggest me about implementing this in java program? Thanks, -Vijay

    Read the article

  • Type hinting in Python

    - by pingvinus
    I'm studying Python after a lot of PHP experience and it would be handy to have type-hinting in Python. Looks like eclipse + pydev doesn't support this. Any suggestions? For example, I want my IDE to show function docstrings and types, when I use it, like: def f(x: int) -> int: r"""Adds 3 to x""" return x + 3 f( #and now IDE shows everything about types

    Read the article

  • For-loops in python

    - by Znarkus
    What is the best way of doing this in Python? for (v = n / 2 - 1; v >= 0; v--) I actually tried Google first, but as far as I can see the only solution would be to use while.

    Read the article

  • Python OOP and lists

    - by Mikk
    Hi, I'm new to Python and it's OOP stuff and can't get it to work. Here's my code: class Tree: root = None; data = []; def __init__(self, equation): self.root = equation; def appendLeft(self, data): self.data.insert(0, data); def appendRight(self, data): self.data.append(data); def calculateLeft(self): result = []; for item in (self.getLeft()): if (type(item) == type(self)): data = item.calculateLeft(); else: data = item; result.append(item); return result; def getLeft(self): return self.data; def getRight(self): data = self.data; data.reverse(); return data; tree2 = Tree("*"); tree2.appendRight(44); tree2.appendLeft(20); tree = Tree("+"); tree.appendRight(4); tree.appendLeft(10); tree.appendLeft(tree2); print(tree.calculateLeft()); It looks like tree2 and tree are sharing list "data"? At the moment I'd like it to output something like [[20,44], 10, 4], but when I tree.appendLeft(tree2) I get RuntimeError: maximum recursion depth exceeded, and when i even won't appendLeft(tree2) it outputs [10, 20, 44, 4] (!!!). What am I missing here? I'm using Portable Python 3.0.1. Thank you

    Read the article

  • Does code in the constructor add to code in subclass constructors?

    - by Jeremy Rudd
    Does code in the constructor add to code in subclass constructors? Or does the subclass's constructor override the superclass? Given this example superclass constructor: class Car{ function Car(){ trace("CAR") } } ...and this subclass constructor: class FordCar extends Car{ function FordCar(){ trace("FORD") } } When an instance of FordCar is created, will this trace "Car" and "Ford" ??

    Read the article

  • vb.net getsettings

    - by PandaNL
    Hello, I need a form width a checkbox "Don't show this again" for my winform, but how can i make this so when my Form1 loads it checks the state of the checkbox using the getsettings option? How can is save the checkbox state to the registery? and how do i get the state? If Form2.Checkbox.checked = Getsettings() Then Form2.showdialog Else Goto Skip End IF Skip:

    Read the article

  • Numerating Comments

    - by John
    The code below prints out all comments for a given "submissionid" in chronological order. How could I numerate these comments? (In other words, how do I print out a "1." next to the oldest comment, a "2." next to the second-oldest comment, etc.?) $submission = mysql_real_escape_string($_GET['submission']); $submissionid = mysql_real_escape_string($_GET['submissionid']); $sqlStr = "SELECT comment.comment, comment.datecommented, login.username FROM comment LEFT JOIN login ON comment.loginid=login.loginid WHERE submissionid=$submissionid ORDER BY comment.datecommented ASC LIMIT 100"; $result = mysql_query($sqlStr); $arr = array(); echo "<table class=\"commentecho\">"; while ($row = mysql_fetch_array($result)) { echo '<tr>'; echo '<td class="commentname1">'.stripslashes($row["comment"]).'</td>'; echo '</tr>'; echo '<tr>'; echo '<td class="commentname2"><a href="http://www...com/sandbox/members/index.php?profile='.$row["username"].'">'.$row["username"].'</a>'.date('l, F j, Y &\nb\sp &\nb\sp g:i a &\nb\sp &\nb\sp \N\E\W &\nb\sp \Y\O\R\K &\nb\sp \T\I\M\E', strtotime($row["datecommented"])).'</td>'; echo '</tr>'; } echo "</table>"

    Read the article

  • Help with copy and deepcopy in Python

    - by Az
    Hi there, I think I tried to ask for far too much in my previous question so apologies for that. Let me lay out my situation in as simple a manner as I can this time. Basically, I've got a bunch of dictionaries that reference my objects, which are in turn mapped using SQLAlchemy. All fine with me. However, I want to make iterative changes to the contents of those dictionaries. The problem is that doing so will change the objects they reference---and using copy.copy() does no good since it only copies the references contained within the dictionary. Thus even if copied something, when I try to, say print the contents of the dictionary, I'll only get the latest updated values for the object. This is why I wanted to use copy.deepcopy() but that does not work with SQLAlchemy. Now I'm in a dilemma since I need to copy certain attributes of my object before making said iterative changes. In summary, I need to use SQLAlchemy and at the same time make sure I can have a copy of my object attributes when making changes so I don't change the referenced object itself. Any advice, help, suggestions, etc.?

    Read the article

  • Why is my simple recusive method's final return value always off by 1?

    - by FrankTheTank
    I'm attempting to create a text-based version of this game: http://www.cse.nd.edu/java/SameGame.html Here is the code I have so far: #include <iostream> #include <vector> #include <ctime> class Clickomania { public: Clickomania(); std::vector<std::vector<int> > board; int move(int, int); bool isSolved(); void print(); void pushDown(); bool isValid(); }; Clickomania::Clickomania() : board(12, std::vector<int>(8,0)) { srand((unsigned)time(0)); for(int i = 0; i < 12; i++) { for(int j = 0; j < 8; j++) { int color = (rand() % 3) + 1; board[i][j] = color; } } } void Clickomania::pushDown() { for(int i = 0; i < 8; i++) { for(int j = 0; j < 12; j++) { if (board[j][i] == 0) { for(int k = j; k > 0; k--) { board[k][i] = board[k-1][i]; } board[0][i] = 0; } } } } int Clickomania::move(int row, int col) { bool match = false; int totalMatches = 0; if (row > 12 || row < 0 || col > 8 || col < 0) { return 0; } int currentColor = board[row][col]; board[row][col] = 0; if ((row + 1) < 12) { if (board[row+1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row+1, col); } } if ((row - 1) >= 0) { if (board[row-1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row-1, col); } } if ((col + 1) < 8) { if (board[row][col+1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col+1); } } if ((col - 1) >= 0) { if (board[row][col-1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col-1); } } return totalMatches; } void Clickomania::print() { for(int i = 0; i < 12; i++) { for(int j = 0; j < 8; j++) { std::cout << board[i][j]; } std::cout << "\n"; } } int main() { Clickomania game; game.print(); int row; int col; std::cout << "Enter row: "; std::cin >> row; std::cout << "Enter col: "; std::cin >> col; int numDestroyed = game.move(row,col); game.print(); std::cout << "Destroyed: " << numDestroyed << "\n"; } The method that is giving me trouble is my "move" method. This method, given a pair of coordinates, should delete all the squares at that coordinate with the same number and likewise with all the squares with the same number connected to it. If you play the link I gave above you'll see how the deletion works on a click. int Clickomania::move(int row, int col) { bool match = false; int totalMatches = 0; if (row > 12 || row < 0 || col > 8 || col < 0) { return 0; } int currentColor = board[row][col]; board[row][col] = 0; if ((row + 1) < 12) { if (board[row+1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row+1, col); } } if ((row - 1) >= 0) { if (board[row-1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row-1, col); } } if ((col + 1) < 8) { if (board[row][col+1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col+1); } } if ((col - 1) >= 0) { if (board[row][col-1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col-1); } } return totalMatches; } My move() method above works fine, as in, it will delete the appropriate "blocks" and replace them with zeros. However, the number of destroyed (value returned) is always one off (too small). I believe this is because the first call of move() isn't being counted but I don't know how to differentiate between the first call or subsequent calls in that recursive method. How can I modify my move() method so it returns the correct number of destroyed blocks?

    Read the article

  • side effect gotchas in python/numpy? horror stories and narrow escapes wanted

    - by shabbychef
    I am considering moving from Matlab to Python/numpy for data analysis and numerical simulations. I have used Matlab (and SML-NJ) for years, and am very comfortable in the functional environment without side effects (barring I/O), but am a little reluctant about the side effects in Python. Can people share their favorite gotchas regarding side effects, and if possible, how they got around them? As an example, I was a bit surprised when I tried the following code in Python: lofls = [[]] * 4 #an accident waiting to happen! lofls[0].append(7) #not what I was expecting... print lofls #gives [[7], [7], [7], [7]] #instead, I should have done this (I think) lofls = [[] for x in range(4)] lofls[0].append(7) #only appends to the first list print lofls #gives [[7], [], [], []] thanks in advance

    Read the article

  • So do programming languages get updated regularly like everyday applications or are they just x.0 re

    - by Randy
    I was wondering if programming languages and frameworks get updated in small increments or are they just x.0 releases? And if they do how do you keep up on all the changes in every update? I am specifically interested in Objective-C and Cocoa and CocoaTouch. I'm learning from books and online PDF's etc, but often they are at best a few years old. I just would like to know if there have been any changes etc. that should concern me and even if not, inevitably there will be, so where can I look out for them?

    Read the article

  • What is the single most influential book every programmer should read?

    - by NotMyself
    If you could go back in time and tell yourself to read a specific book at the beginning of your career as a developer, which book would it be? I expect this list to be varied and to cover a wide range of things. For me, the book would be Code Complete. After reading that book, I was able to get out of the immediate task mindset and begin to think about the bigger picture, quality and maintainability.

    Read the article

  • Strange Bubble sort behaviour.

    - by user271528
    Can anyone explain why this bubble sort function doesn't work and why I loose number in my output. I'm very new to C, so please forgive me if this is something very obvious I have missed. #include <stdio.h> #include int bubble(int array[],int length) { int i, j; int temp; for(i = 0; i < (length); ++i) { for(j = 0; j < (length - 1); ++j) { if(array[i] array[i+1]) { temp = array[i+1]; array[i+1] = array[i]; array[i] = temp; } } } return 0; } int main() { int array[] = {12,234,3452,5643,0}; int i; int length; length = (sizeof(array)/sizeof(int)); printf("Size of array = %d\n", length); bubble(array, length); for (i = 0; i < (length); ++i) { printf("%d\n", array[i]); } return 0; } Output Size of array = 5 12 234 3452 0 0

    Read the article

  • How to learn flex?

    - by Zenzen
    So I'm starting an internship as a Flex developer in ~2weeks thanks to a friend of mine. The thing is I know squat about Flex - it is an internship after all so I'm supposed to learn there, but nonetheless I want to have some basic understanding of Flex before I start (eventually I want to become a JEE/Flex dev). So my question is simple, which book(s) would you recommend me to start with? Are there any "must have" books, like let's say "Thinking in C++" for C++ etc.? I already heard about a few video tutorials and I will surely check them out but I'd also want to get some decent books.

    Read the article

  • whats the diference between train, validation and test set, in neural networks?

    - by Daniel
    Im using this library http://pastebin.com/raw.php?i=aMtVv4RZ to implement a learning agent. I have generated the train cases, but i dont know for sure what are the validation and test sets, the teacher says: 70% should be train cases, 10% will be test cases and the rest 20% should be validation cases. Thanks. edit i have this code, for training.. but i have no ideia when to stop training.. def train(self, train, validation, N=0.3, M=0.1): # N: learning rate # M: momentum factor accuracy = list() while(True): error = 0.0 for p in train: input, target = p self.update(input) error = error + self.backPropagate(target, N, M) print "validation" total = 0 for p in validation: input, target = p output = self.update(input) total += sum([abs(target - output) for target, output in zip(target, output)]) #calculates sum of absolute diference between target and output accuracy.append(total) print min(accuracy) print sum(accuracy[-5:])/5 #if i % 100 == 0: print 'error %-14f' % error if ? < ?: break

    Read the article

< Previous Page | 75 76 77 78 79 80 81 82 83 84 85 86  | Next Page >