Search Results

Search found 11438 results on 458 pages for 'self imposed homework'.

Page 34/458 | < Previous Page | 30 31 32 33 34 35 36 37 38 39 40 41  | Next Page >

  • Is this an acceptable approach to undo/redo in Python?

    - by Codemonkey
    I'm making an application (wxPython) to process some data from Excel documents. I want the user to be able to undo and redo actions, even gigantic actions like processing the contents of 10 000 cells simultaneously. I Googled the topic, and all the solutions I could find involves a lot of black magic or is overly complicated. Here is how I imagine my simple undo/redo scheme. I write two classes - one called ActionStack and an abstract one called Action. Every "undoable" operation must be a subclass of Action and define the methods do and undo. The Action subclass is passed the instance of the "document", or data model, and is responsible for committing the operation and remembering how to undo the change. Now, every document is associated with an instance of the ActionStack. The ActionStack maintains a stack of actions (surprise!). Every time actions are undone and new actions are performed, all undone actions are removed for ever. The ActionStack will also automatically remove the oldest Action when the stack reaches the configurable maximum amount. I imagine the workflow would produce code looking something like this: class TableDocument(object): def __init__(self, table): self.table = table self.action_stack = ActionStack(history_limit=50) # ... def delete_cells(self, cells): self.action_stack.push( DeleteAction(self, cells) ) def add_column(self, index, name=''): self.action_stack.push( AddColumnAction(self, index, name) ) # ... def undo(self, count=1): self.action_stack.undo(count) def redo(self, count=1): self.action_stack.redo(count) Given that none of the methods I've found are this simple, I thought I'd get the experts' opinion before I go ahead with this plan. More specifically, what I'm wondering about is - are there any glaring holes in this plan that I'm not seeing?

    Read the article

  • jQuery to add vertical scroll bar for a fixed height div container

    - by Michael Mao
    Hi all: This is uni homework so sorry about :my password protected url Please enter usersame as "uts" and password as "10479475", without the wrapper quotes. It it almost completed, please follow simple steps to see where my problem dwells: step1: click on any continent highlighted on world map; step2: click on any city marked on continent map; step3: enter quantity ranging from 1 to 6 into the upper-right table; step4 : there you go, in the table below, once row is equal or greater than 3, then the size of table starts to "overlap" on top of the footer section and continues to grow, which is not what I want. I want to achieve the effect that the table size has a limited max-height, so once actual height exceeds the threshold, then I can have a vertical scroll bar so to "stack up" my table and not to break the overall structure. It turns out that my lazy initial design now gets myself stuck in a problem... Any suggestion and hint on how to get this?

    Read the article

  • Write a function that compares two strings and returns a third string containing only the letters th

    - by Pritam
    Hi All, I got this homework. And have solved it in following way. I need your comments whether it is a good approach or I need to use any other data sturcture to solve it in better way. public string ReturnCommon(string firstString, string scndString) { StringBuilder newStb = new StringBuilder(); if (firstString != null && scndString != null) { foreach (char ichar in firstString) { if (!newStb.ToString().Contains(ichar) && scndString.Contains(ichar)) newStb.Append(ichar); } } return newStb.ToString(); }

    Read the article

  • C Programming - Convert an integer to binary

    - by leo
    Hi guys - i was hopefully after some tips opposed to solutions as this is homework and i want to solve it myself I am firstly very new to C. In fact i have never done any before, though i have previous java experience from modules at university. I am trying to write a programme that converts a single integer in to binary. I am only allowed to use bitwise operations and no library functions Can anyone possibly suggest some ideas about how i would go about doing this. Obviously i dont want code or anything, just some ideas as to what avenues to explore as currenty i am a little confused and have no plan of attack. Well, make that a lot confused :D thanks very much

    Read the article

  • Shorten array length once element is remove in Java.

    - by lupin
    Note: Following is my homework/assignment, feel free not to answer if you will. I want to delete/remove an element from an String array(Set) basic, I'm not allowed to use Collections..etc. Now I have this: void remove(String newValue) { for ( int i = 0; i < setElements.length; i++) { if ( setElements[i] == newValue ) { setElements[i] = ""; } } } I does what I want as it remove the element from an array but it doesn't shorten the length. The following is the output, basically it remove the element indexed #1. D:\javaprojects>java SetsDemo Enter string element to be added A You entered A Set size is: 5 Member elements on index: 0 A Member elements on index: 1 b Member elements on index: 2 hello Member elements on index: 3 world Member elements on index: 4 six Set size is: 5 Member elements on index: 0 A Member elements on index: 1 Member elements on index: 2 hello Member elements on index: 3 world Member elements on index: 4 six lupin

    Read the article

  • How to define clock input in Xilinx

    - by seventeen
    Hey, I have almost no experience with Xilinx. I have a group project for a Digital Logic course that is due soon, where my partner, who was supposed to take care of the Xilinx simulations decided to bail on me. So here I am trying to figure it out last minute. I have designed a synchronous counter using a few JK Flip Flops and I need to define the CLK input for the FJKCs. I have drawn up the correct schematic, but I cannot figure out how to define a clock input. Any help appreciated, and yes, this is homework. I just can't find any basic xilinx documentation/tutorials online and I honestly don't have time to learn the whole IDE.

    Read the article

  • GoTo statements, and alternatives (help me please im new) (VB.net)

    - by qais
    Basically I posted a code snippet on a forum asking for help and people pointed out to me that using GoTo statements is very bad programming practise so I'm just wondering, why is it bad? And also what alternative is there to use, like for example in this program ive done for homework the user has to input their date of birth and if the month/date/year are invalid or unrealistic(using if statements checking the integer inputs size, if theres any better way to do this i'd appreciate if you could tell me that also :D) then how would i be able to loop back to ask them again? heres a little extract of my code 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

  • Is this an example of polymorphism?

    - by computer-science-student
    I'm working on a homework assignment (a project), for which one criterion is that I must make use of polymorphism in a way which noticeably improves the overall quality or functionality of my code. I made a Hash Table which looks like this: public class HashTable<E extends Hashable>{ ... } where Hashable is an interface I made that has a hash() function. I know that using generics this way improves the quality of my code, since now HashTable can work with pretty much any type I want (instead of just ints or Strings for example). But I'm not sure if it demonstrates polymorphism. I think it does, because E can be any type that implements Hashable. In other words HashTable is a class which can work with (practically) any type. But I'm not quite sure - is that polymorphism? Perhaps can I get some clarification as to what exactly polymorphism is? Thanks in advance!

    Read the article

  • How to Access a Private Variable?

    - by SoulBeaver
    This question isn't meant to sound as blatantly insulting as it probably is right now. This is a homework assignment, and the spec sheet is scarce and poorly designed to say the least. We have a function: double refuel( int liter, GasStation *gs ) { // TODO: Access private variable MaxFuel of gs and decrement. } Sound simple enough? It should be, but the class GasStation comes with no function that accesses the private variable MaxFuel. So how can I access it anyway using the function refuel? I'm not considering creating a function setFuel( int liter ) because the teacher always complains rather energetically if I change his specification. So... I guess I have to do some sort of hack around it, but I'm not sure how to go about this without explicitely changing the only function in GasStation and giving it a parameter so that I can call it here. Any hints perhaps?

    Read the article

  • SQL syntax Newbie student

    - by sammysmall
    Describe the output of the following SQL query: select custId, name from customer where region = "New York" UNION select cust.custId, cust.name from customer cust where cust.custId IN (select cust_order.custId from customer_order cust_order, company_employee comp_emp where cust_order.salesEmpId = comp_emp.empId AND comp_emp.name = 'DANIEL'); My question is: at line from customer cust is cust referring to a column in the customer table... This is a homework question I have identified the components leading up to this line and I think that cust is a column in the customer table... I am not asking for an overall solution just a bit of encouragement if I am on the right track...

    Read the article

  • Trying to draw 2 objects on screen and store the selected item names in an array

    - by thefonso
    Ok...this is a homework question, here is what i'm asked to do.... "Allow the user to draw two Shapes, which when instantiated, get put into the array myShapes...(store the shapes in the createShape() method." I want to know if I'm going in the right direction. Do I need to modify only Model.java or GUIDemo.java as well? Am I sufficient in thinking of only storing the values for the array via a loop inside my createShape() method? How do I go a bout checking to see if things work so far. There are many steps for this homework project after this one but i'm stuck here. Please point me in the right direction. The array myShapes lives inside my model class inside Model.java: package model; import java.awt.Color; import java.awt.Container; import shapes.Line; import shapes.Oval; import shapes.Rectangle; import shapes.Shape; import shapes.Triangle; import interfaces.Resettable; public class Model implements Resettable { private Container container; private String message; public final static String DRAW = "Draw"; public final static String MOVE = "Move"; public final static String REMOVE = "Remove"; public final static String RESIZE = "Resize"; public final static String FILL = "Fill"; public final static String CHANGE = "Change"; public final static String RECTANGLE = "Rectangle"; public final static String OVAL = "Oval"; public final static String LINE = "Line"; public final static String TRIANGLE = "Triangle"; private String action = DRAW; private boolean fill = false; public static String[] selections = {"Rectangle", "Oval", "Line", "Triangle"}; //project 9 begin public Shape[] myShapes = new Shape[2]; //project 9 stop private String currentShapeType; private Shape currentShape; public Color lineColor; private Color fillColor = Color.gray; public Shape createShape() { if(currentShapeType == RECTANGLE){ currentShape = new Rectangle(0, 0, 0, 0, lineColor, fillColor, fill); } if(currentShapeType == OVAL) { currentShape = new Oval(0,0,0,0, lineColor, fillColor, fill); } if(currentShapeType == LINE) { currentShape = new Line(0,0,0,0, lineColor, fillColor, fill); } if(currentShapeType == TRIANGLE) { currentShape = new Triangle(0,0,0,0, lineColor, fillColor, fill); } //project 9 start if(myShapes[0] == null) { myShapes[0]=currentShape; } else { myShapes[1]=currentShape; } //project 9 stop return currentShape; } public Shape getCurrentShape() { return currentShape; } public String getCurrentShapeType(){ return currentShapeType; } public void setCurrentShapeType(String shapeType){ currentShapeType = shapeType; } public Model(Container container) { this.container = container; } public void repaint() { container.repaint(); } public void resetComponents() { action = DRAW; currentShape = null; if (container instanceof Resettable) { ((Resettable) container).resetComponents(); } } public String getAction() { return action; } public void setAction(String action) { this.action = action; } public boolean isFill() { return fill; } public void setFill(boolean fill) { this.fill = fill; } public void setMessage(String msg) { this.message = msg; } public String getMessage() { return this.message; } public Color getLineColor() { return this.lineColor; } public void setLineColor(Color c) { this.lineColor = c; } public String toString() { return "Model:\n\tAction: " + action + "\n\tFill: " + fill; } } The application is run from GUIDemo.java: package ui.applet; import interfaces.Resettable; import java.applet.Applet; import java.awt.Graphics; import event.ShapeMouseHandler; import shapes.Shape; //import ui.panels.ButtonPanel; import ui.panels.ChoicePanel; import ui.panels.MainPanel; import model.Model; @SuppressWarnings("serial") public class GUIDemo extends Applet implements Resettable { MainPanel mainPanel; Model model; ChoicePanel choicePanel; public void init() { resize(600,400); model = new Model(this); choicePanel = new ChoicePanel(model); mainPanel = new MainPanel(model); this.add(choicePanel);//this is the drop down list this.add(mainPanel);//these are the radio buttons and reset button ShapeMouseHandler mouseHandler = new ShapeMouseHandler(model); addMouseListener(mouseHandler); addMouseMotionListener(mouseHandler); } public void paint(Graphics g) { Shape shape; shape = model.getCurrentShape(); if(shape != null) { shape.draw(g); } System.out.println(model); System.out.println(shape); } public void resetComponents() { mainPanel.resetComponents(); choicePanel.resetComponents(); } }

    Read the article

  • Rewrite probabilities as boolean algebra

    - by Magsol
    I'm given three binary random variables: X, Y, and Z. I'm also given the following: P(Z | X) P(Z | Y) P(X) P(Y) I'm then supposed to determine whether or not it is possible to find P(Z | Y, X). I've tried rewriting the solution in the form of Bayes' Theorem and have gotten nowhere. Given that these are boolean random variables, is it possible to rewrite the system in terms of boolean algebra? I understand that the conditionals can be mapped to boolean implications (x -> y, or !x + y), but I'm unsure how this would translate in terms of the overall problem I'm trying to solve. (yes, this is a homework problem, but here I'm much more interested in how to formally solve this problem than what the solution is...I also figured this question would be entirely too simple for MathOverflow)

    Read the article

  • Outputting variable values in x86?

    - by Airjoe
    Hello All- I'm working on a homework assignment in x86 and it isn't working as I expect (surprise surprise!). I'd like to be able to output values of variables in x86 functions to ensure that the values are what I expect them to be. Is there a simple way to do this, or is it very complex? For what it's worth, the x86 functions are being used by a C file and compiled with gcc, so if that makes it simpler that is how I'm going about it. Thanks for the help.

    Read the article

  • SQL Server CTE referred in self joins slow

    - by Kharlos Dominguez
    Hello, I have written a table-valued UDF that starts by a CTE to return a subset of the rows from a large table. There are several joins in the CTE. A couple of inner and one left join to other tables, which don't contain a lot of rows. The CTE has a where clause that returns the rows within a date range, in order to return only the rows needed. I'm then referencing this CTE in 4 self left joins, in order to build subtotals using different criterias. The query is quite complex but here is a simplified pseudo-version of it WITH DataCTE as ( SELECT [columns] FROM table INNER JOIN table2 ON [...] INNER JOIN table3 ON [...] LEFT JOIN table3 ON [...] ) SELECT [aggregates_columns of each subset] FROM DataCTE Main LEFT JOIN DataCTE BananasSubset ON [...] AND Product = 'Bananas' AND Quality = 100 LEFT JOIN DataCTE DamagedBananasSubset ON [...] AND Product = 'Bananas' AND Quality < 20 LEFT JOIN DataCTE MangosSubset ON [...] GROUP BY [ I have the feeling that SQL Server gets confused and calls the CTE for each self join, which seems confirmed by looking at the execution plan, although I confess not being an expert at reading those. I would have assumed SQL Server to be smart enough to only perform the data retrieval from the CTE only once, rather than do it several times. I have tried the same approach but rather than using a CTE to get the subset of the data, I used the same select query as in the CTE, but made it output to a temp table instead. The version referring the CTE version takes 40 seconds. The version referring the temp table takes between 1 and 2 seconds. Why isn't SQL Server smart enough to keep the CTE results in memory? I like CTEs, especially in this case as my UDF is a table-valued one, so it allowed me to keep everything in a single statement. To use a temp table, I would need to write a multi-statement table valued UDF, which I find a slightly less elegant solution. Did some of you had this kind of performance issues with CTE, and if so, how did you get them sorted? Thanks, Kharlos

    Read the article

  • XSLT: How to remove the self-closed elment

    - by Daoming Yang
    I have a large xml file which contents a lot of self-closed tags. How could remove all them by using XSLT. eg. <?xml version="1.0" encoding="utf-8" ?> <Persons> <Person> <Name>user1</Name> <Tel /> <Mobile>123</Mobile> </Person> <Person> <Name>user2</Name> <Tel>456</Tel> <Mobile /> </Person> <Person> <Name /> <Tel>123</Tel> <Mobile /> </Person> <Person> <Name>user4</Name> <Tel /> <Mobile /> </Person> </Persons> I'm expecting the result: <?xml version="1.0" encoding="utf-8" ?> <Persons> <Person> <Name>user1</Name> <Mobile>123</Mobile> </Person> <Person> <Name>user2</Name> <Tel>456</Tel> </Person> <Person> <Tel>123</Tel> </Person> <Person> <Name>user4</Name> </Person> </Persons> Note: there are thousands of different elements, how can I programmatically remove all the self-closed tags. Another question is how to remove the empty element such as <name></name> as well. Can anyone help me on this? Many thanks.

    Read the article

  • SQL Server 2005 Create Table with Column Default value range

    - by Matt
    Trying to finish up some homework and ran into a issue for creating tables. How do you declare a column default for a range of numbers. Its reads: "Column Building (default to 1 but can be 1-10)" I can't seem to find ...or know where to look for this information. CREATE TABLE tblDepartment ( Department_ID int NOT NULL IDENTITY, Department_Name varchar(255) NOT NULL, Division_Name varchar(255) NOT NULL, City varchar(255) default 'spokane' NOT NULL, Building int default 1 NOT NULL, Phone varchar(255) ) I tried Building int default 1 Between 1 AND 10 NOT NULL, that didn't work out I tried Building int default 1-10, the table was created but I don't think its correct.

    Read the article

  • PHP Error, is it resolvable, or a language bug?

    - by rls
    Given the following code $c= new SoapClient('http://www.webservicex.net/CurrencyConvertor.asmx?WSDL'); $usa = "USD"; $eng = "GBP"; doing a __getTypes on the client gives me Array ( [0] => struct ConversionRate { Currency FromCurrency; Currency ToCurrency; } [1] => string Currency [2] => struct ConversionRateResponse { double ConversionRateResult; } ) if i then do $calculation = $c->ConversionRate($usa, $eng); and print calculation i get an error about Catchable fatal error: Object of class stdClass could not be converted to string Is there a specific way i should be printing this out, or i it a bug, from researching / googling many people seem to have a problem but i cant find a suitbale solution, other than downgrading php, which isnt a solution for me as i am doing this as homework and its running off of a college server

    Read the article

  • Self Authenticating Links in Django

    - by awolf
    In my web app I would like to be able to email self-authenticating links to users. These links will contain a unique token (uuid). When they click the link the token being present in the query string will be enough to authenticate them and they won't have to enter their username and password. What's the best way to do this?

    Read the article

  • Java / Android self naming

    - by ngreenwood6
    I am about to start developing an Android application and had a question if in Java there self naming. For instance say I had a variable named dog that held the value of scruffy. Could I then create a variable named scruffy from that variable. In PHP it would be $$dog. That would make a variable with the name scruffy. If this is possible please provide example

    Read the article

  • how to solve nested list programs [closed]

    - by riya
    write a function to get most popular car that accepts a car detail as input and returns the most popular car name along with its average rating .Each element of car details list is a sublist that provides the below information about a car (a)name of a car(b)car price (c) list of ratings obtained by car from various agencies.Incase two cars have the same average rating then the car with the lesser price qualifies as most popular car? here's my solution-: (define-struct cardetails ("name" price list of '(ratings)) (define car1 (make-cardetails "toyota" 123 '( 1 2 3))) (define car2 (make-cardetails "santro" 321 '( 2 2 3))) (define car3 (make-cardetails "toyota" 100 '( 1 2 3))) (define cardetailslist(list(car1) (car2)(car 3))) (let loop ((count 0)) (let (len (length cardetailslist)) (if(< count len) (string-ref (string-ref n)0) now please tell me how to find maximum average and display car name.it's not a homework question tomorrow is my test and we have not been taught this concept in class although it is very important from test point of view

    Read the article

  • C++: concatenate ints in an array?

    - by Nate
    As part of a homework assignment I need to concatenate certain values in an array in C++. So, for example if I have: int v[] = {0,1,2,3,4} I may need at some point to concatenate v[1] - v[4] so that I get an int with the value 1234. I got it working using stringstream, by appending the values onto the stringstream and then converting back to an integer. However, throughout the program there will eventually be about 3 million different permutations of v[] passed to my toInt() function, and the stringstream seems rather expensive (at least when dealing with that many values). it's working, but very slow and I'm trying to do whatever I can to optimize it. Is there a more optimal way to concatenate ints in an array in C++? I've done some searching and nearly everywhere seems to just suggest using stringstream (which works, but seems to be slowing my program down a lot). EDIT: Just clarifying, I do need the result to be an int.

    Read the article

< Previous Page | 30 31 32 33 34 35 36 37 38 39 40 41  | Next Page >