C++ :: Adding Additional Functions To STL Vector Class
Jan 30, 2013How would I add my own function to the vector class?
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Visual C++ :: Adding Rational Number Using Only Class Functions
Feb 22, 2015I'm having trouble finishing this program. What I'm trying to do is create a class for Rational numbers. Get input from user for denominator and numerator. Store the numbers without a sign, and for the sign store it separately in char. I'm not supposed to use accessor functions. The part that I can't seem to know how to do is use the info that was stored in the addUp function. This function need to add two rational numbers. i need to make this function general enough that it can handle two fractions, or a fraction and a whole number, or two whole numbers. What I already have here is readin function which reads in the numerator and denominator. setnumerator and setdenominator to assign positive values. setsign should get the sign of the fraction. Finally addUp should addUp which I explained before. I have some ideas about writing the tests, but can't seem to know how to implement it to the program. The main program is still empty but all I'm supposed to do there is call the class functions.
Code:
#include <iostream>
using namespace std;
class Rational {
private:
int numerator, denominator;
char sign;
[Code] .....
C++ :: Adding Items From File To Vector Of Class
Oct 10, 2013how to add a list of information from a file to a vector of a class. Here is my code:
Champion_Info.h
#ifndef CHAMPION_INFO_H_INCLUDED
#define CHAMPION_INFO_H_INCLUDED
#include <vector>
#include <string>
[Code].....
C++ :: Accessing Class Functions In A Vector?
Jul 24, 2013How I can use class functions in a vector. I have 2 classes:
Gamemode class
bullets class
Inside the Gamemode class I declared: vector<bullets> Bullet and bullets * b.
If the user presses the shoot button a new bullets class will be added to the Bullet vector:
b = new bullets;
Bullet.push_back(b)
Bow I'd like to check all objects in the Bullet vector for the collision() function inside the bullets class.
I already set up a for loop which counts from 0 to the end of the vector:
for( int i=0;i<Bullet.size;i++)
{
}
My idea was to do something like:
if(Bullet[i].collision()) then erase Bullet[i]
But that doesn't work...
C :: Adding New Functions
Jul 3, 2014I am new to c and I have come across a problem when adding other functions to a programme and printing the values. The question I am attempting to solve is :
The following function computes ex by summing the Taylor series expansion to n terms. Write a program to print a table of ex using both this function and the exp() function from the math.h library, for x = 0 to 1 in steps of 0.1. The program should ask the user what value of n to use.
double taylor(double x, int n) {
int i;
double sum = 1.0;
double term = 1.0;
for (i=1; i<=n; i++) {
/*Or we could have written: */
term = term * x / i; /* term *= x / i; */
sum = sum + term; /* sum += term; */
}
return sum;
}
My code is
Code:
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
/*Taylor series for e*/
[code]....
code prints out the values for exp, but it gets stuck in the Taylor function and I'm not sure how to solve it.
C++ :: Adding Sums With Void Functions
May 3, 20131) This first function initializes an array of 30 components so that the first 15 components are equal to the square of the index value and the last 15 components are equal to the index value multiplied by 3.
2) The second function processes the array by finding the sum of the first 15 components and the sum of the last 15 components to determine which sum is bigger. The output to the screen should do the following:
a)State “The sum of the first 15 components is:” and then show the sum.
b)State “The sum of the last 15 components is:” and then show the sum.
c)State which of the two resulted in the greater sum or if the two sums were equal.
Function: The program uses two subroutines. One to initialize an array and the other to process the array and print to screen results:
#include <iostream>
#include <iomanip>
// Include any other header files you may need.
const int ARRAY_SIZE = 30;
void initialize ( double list[], int index );
void square ( double list[], int index );
void threeTimes ( double list[], int index );
void output ( const double list[], int index );
[Code] .....
C/C++ :: How To Access Linked List Functions From Stack Class Without Functions
Mar 20, 2014I'm a little confused by my programming assignment this week. I've been working at it Wednesday and I've made progress but I'm still confused as to how I'm supposed to do this. The class I made is called Stack, and it's derived from a template class called StackADT. We also utilize a class called unorderedLinkedList, which is derived from a class called linkedList.
We're supposed to implement all of the virtual functions from stackADT in the Stack class. The Stack data is stored in a an unorderedLinkedList, so what I'm confused by is how to implement a few of the Stack functions because there are no functions in unorderedLinkedList which we could call to manipulate the data.
As you can see from my attached code, I'm really confused by how I'm supposed to implement the pop() and top() functions, and I also think my initializeList() function is wrong. We don't have any similar functions in unorderedLinkedList to call, so I'm at a loss of how i'd access my unorderedLinkedList. My initial thought was to call the similar functions in the class that unorderedLinkedList was derived from, linkedList, but I'm unsure of this is what we're supposed to do, or if theres actually a way to access my unorderedLinkedList without having to use the functions from the base class.
NOTE: We're not allowed to modify stackADT, unorderedLinkedList, and linkedList.
Stack.h
#include "stackADT.h"
#include "unorderedLinkedList.h"
template<class Type>
class Stack: public stackADT<Type>{
template <class T>
struct nodeType
{
T info;
nodeType<T> *link;
[Code]...
C/C++ :: Array Of Functions Pointing To In Class Functions With Arduino
May 3, 2013At the moment im trying out with pointing to an array of functions. I got this working as following:
typedef void (* functionPtr) ();
functionPtr functions[2][2]={{do11,do12}, {do21,do22}};
void do11(){DEBUG_PRINTLN("11");}
void do12(){DEBUG_PRINTLN("12");}
void do21(){DEBUG_PRINTLN("21");}
void do22(){DEBUG_PRINTLN("22");}
void loop(){
A=0;
B=1;
functions[A][b]();
}
But now I'm trying to use this to point to a function inside a class so instead of do11, i want to be able to point to Basic.Do11. Somehow this doesnt work and I keep on getting this message:
error: argument of type 'void (Basic::)()' does not match 'void (*)()'
C++ :: 2D Vector Adding Columns
Apr 10, 2014I have a basic question regarding 2d vectors. The following code makes a 2d vector and fills it with a matrix of integers. The vector tempVector3 gets added as a new row to the matrix. But what if I wanted to add the tempVector3 as a new column instead. How would this be done in the simplest way?
#include<iostream>
#include<vector>
int main(){
std::vector<std::vector<int>> numbers;
std::vector<int> tempVector1;
tempVector1.push_back(2);
[Code] ....
C++ :: Printing Vector Adding New Line
Oct 10, 2013I have a vector of structs.
struct myStruct{
string text;
int num;
};
vector<myStruct> foo;
And I am attempting to print the text followed by a space, then the number. Like so:
foobar 5
But when trying to print my vector using
ofstream outputFile;
outputFile.open ("file.txt");
for(int i = 0; i < foo.size(); i++) {
outputFile << foo[x].text << " " << foo[x].num << endl;
}
It prints like
foobar
5
moretext
8
With an extra newline and space. How to get rid of it and print it on the same line.
I have checked that text does not include new line character at the end. Also, it seems to print correctly using cout, but not print correctly to output file...
C++ :: Adding Int Type Into Vector - Runtime Error
Feb 1, 2013I am adding int type into vector called "vi" several times like this.
std::vector<int> vi;
void addFunc(int *a, int cnt) {
vi.erase(vi.begin(), vi.end());
vi.clear();
for(int i=0; i<cnt; i++)
vi.push_back(a[i]);
}
and I call the addfunc N times every sec.
And sometimes it has runtime error on vi.push_back line.
(called stack says "_CrtIsValidHeapPointer")
C++ :: Reading Unknown Number Of Inputs And Adding Them In Vector
Jan 16, 2013Consider the following piece of Code:
int ReadNumbers() {
int num;
vector<int> x;
cout << "Enter Numbers" << '
[Code] ....
The while loop is expected to terminate when the user provides an Invalid Input. But this while loop behaves unexpectedly when the user provides a 'Newline' input (by pressing Enter) and becomes an infinite loop. How can I prevent this from happening? Also I've heard that expecting invalid inputs isn't good code design. Is this true? If yes, then how can I solve my question without expecting Invalid Inputs?
C++ :: Filling Vector From A File - Adding Empty Element At The End
Apr 20, 2014I'm having a problem filling a vector from a file. Basically, it is adding an empty element at the end. I'm new to Qt and haven't worked with file streams much so how to stop the stream before it adds the extra element.
void gui::get_data() {
mileage.clear();
QFile file(file_label->text() + ".txt");
QTextStream in(& file);
float m;
float g;
QString d;
[Code] ....
But, if I add another element to the vector and write that the file look like this.
//file after adding element
132654 0 02132014
132654 0 02132014
0 0
132998 22 02202014
I have it set to append at the moment so that is why the first line is repeated. I figure the problem is with if(in.atEnd()). I could fix it by deleting the last element right after adding it, but that seems like more of a hack than anything else.
C++ :: Create Class Vector As Template And Define Operations On Vector?
May 13, 2013I need to create a class vector as a template and define operations on vectors.
And this is what I made.
#include<iostream>
using namespace std;
template<class T>
[Code].....
C++ :: Calling Derived Class Functions In A Function With Parameter Of Base Class
Mar 30, 2013Say I have 3 classes:
class Player {
public:
virtual func1();
[code]....
Say in my main class, I have a function fight(Player p1, Player p2) and I would like to do something like this in the fight function, given that p1 is the human and p2 is the computer:
//function fight()
fight(Player p1, Player p2) {
p1.func2();
}
//using function fight()
fight(human, computer);
When I compile the program, I got this: error: ‘class Player’ has no member named 'func2()' What can I do to allow p1 to call func2 inside fight()? I'm not allowed to use pointers as the parameter for fight() and have to use the signature fight(Player p1, Player p2).
C++ :: Size Of Derived Class With Overriding Virtual Functions From Base Class?
Jan 21, 2014The compiler creates virtual table for the base class and also for the derived class whether we override it or not.
That means each class has separate virtual table. when we get the size of the each class with out any data members... the size of base is -- 4 bytes(64 bit) and the size of derived is -- 1
The size of base class 4 is correct since it creates the virtual pointer internally and its size is member data + virtual pointer, but it in this case I have included any data members so it has given 4 byts.
But why in case of derived is 1 byte, since it the derived class has overridden the virtual function from base, this will also contains the virtual pointer which will be pointing to derived class Vtable, it the size of the class suppose to be 4 instead of 1 byte.
#include<iostream>
class A{
public:
[Code].....
C++ :: Calling Functions - Vector Of Pointers
Mar 27, 2013I have a vector of pointers inside a seperate Exam class.
vector <Question* > question_list
The Question class is my base class in which I have derived sub classes for the different types of questions (MultipleChoice, LongAnswer, etc.). I am using my vector to hold the different types of questions.
in each of those classes I have virtual "write" functions in both the base and the derived classes, that write to a file differing for each type of question.
My problem now is calling the write function from a Exam function. I've tried several methods, such as:
for (size_t i = 0; i < question_list.size(); i++) {
question_list[i].write(testfile.c_str());
}
but it comes with two errors: "error C2228:left of '.write' must have class/struct/union" along with "IntelliSense: expression must have class type"
I have made a write function for the exam class as well but am not sure what it should include since the Exam class is not a derived class of the Question class.
C++ :: How To Access Vector Of Queues In Two Functions
Jan 20, 2013I have the following code which will find the minimum size queue among a vector of queues and the minimimum size queue will enqueue(push) the int
std::vector<std::queue<int> > q
void enqueue(){
int min_index = 1;
std::size_t size = q.size();
for( i=2; i<size; i++) //accessing loop of queues
if(q[min_index].size() > q[i].size())
min_index = i; // Now q[min_index] is the shortest queue
q[min_index].push(int)
}
Now my another paradigm is to do the dequeue(pop) operation in another function(shown below), bt i need to access all vector of queues declared in enqueue() function. how can i access the loop of queues given in the enqueue() function?
void dequeue(){
//q.pop operation , access all the queues in the loop of queues
}
willq[i].pop(int);
Access all the queues in the enqueue function and does the pop operation?
C/C++ :: Access Derived Classes Functions On A Vector
Jan 19, 2014I need to access the functions of the derived classes from a vector of objects of base classes (can't believe I wrote it). Here a Diagram for you to understand:
So as you see, I need the function Use() from the Usable class, to be able to be called from the vector like:
inventory.at(x)->Use()
C/C++ :: Adding Properties To A Class?
Jun 29, 2014I had written a "DLL" in VB.NET a year or two ago to read and set MP3 tags. I want to write this exact same library in C++ so I can convert it in my droid project, and to get a hands on introduction to C++. So far this attempt has been a total mind melt!
I am finally wrapping my head around .cpp and .h files so there is light at the end of this tunnel. Here is my problem now:
I wrote the VB project with properties for each tag in the MP3 file, then I could get and set them - easy stuff.
When I try this in C++ I get compile error: a property can only appear within the definition of a managed type. I can usually stumble through Google searches and figure out this type of stuff on my own, but this one is stumping me -- I think I am missing some fundamental stuff here.
My code:
// MP3Tags.h
#pragma once;
#include <string>
using namespace std;
using namespace System::IO;
[Code]....
C# :: Adding To Array From Different Class
Jan 10, 2015I have an inventory array in a class called inventory. This class is in a different program. How do I access and add to this array for my main program?
View 1 Replies View RelatedC++ :: Additional Library Installation Options
Aug 5, 2013I have been reading up, and it seems that all I need to do to finish up the installation of a library is to add in the search path for the library upon compile time.
Of course, I also read that directly copying the lib files can work too, but that may result in the over-writing of necessary files...
I read a more thorough document on mingw's linking processes and discovered that I could create a folder, install the library in that folder, and add the folder as a search path for mingw (so, basically, all i have to do is install all my libraries under that folder).
C++ :: Cout Double Or Float Without Additional 0?
Jun 30, 2013I m working calculating stuff in files, input and output data, etc..., the question is the following: I output double numbers with:
myFIle << fixed << setprecision(10) << double;
The problem i got is that when a numer is like 193123.2 it prints like 193123.200000..., so finally, ¿how can i print it with any additional 0 that i need?.
C++ :: Adding Arrays And Matrix To A Class?
Feb 5, 2014I'd like to start out by adding an array to a C++ class. I'd like to be able to reference the array using a class object that I create, for example:
Class is Stone.
Stone Bob is an instance of "stone" that I name "Bob".
"Bob.array[1] = "granite";" tells the compiler that the second element in the array (with the first being the zeroth element) is a string containing "granite".
I'll eventually want to extend this to an n x m matrix within the "stone" class that can be referenced as: Bob.matrix[1][3]="lignite";
I tried to make this work using a text again and again last night to no avail. My code is below.
NOTE: Since I am dynamically allocating memory space, I'd like to avoid memory leaks when using this class with dynamically allocated arrays and matrices. Not sure how to do this. Also need some insight into "destructor", and why my simple version reduced to a comment below doesn't seem to please the compiler.
CODE FOLLOWS:
Code:
// AINOW.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <string>
using std:: string;
using std:: cout;
using std:: endl;
using std:: cin;
[code]....
C++ :: Adding New Options To String Class
Oct 8, 2014I'm giving the replace option to my string:
void replace(string oldstring, string newstring) {
int stroldstringpos=b.find(oldstring);
b.replace(stroldstringpos,newstring.length(),newstring);
}
i have 1 error in these function that i'm confused. imagine the newstring size is more big than the oldstring, how can change the string, but only change the oldstring and add what left?
see these:
String test="hi hello world";
test.replace("hi","hello");
the result must be:
hello hello world
how can i change the replace function for it?
C++ :: Adding Two Objects Of Class (Matrix)
Feb 13, 2013I am trying to add matrices a and b. I am getting an error in the "add" function, probably because I have m[i] in it, and m is not an array. What is the correct way of writing the "add" member function here?
Also, although the "read" and "write" member functions of the class are working just fine, do you think there is a better way of writing them?
Code:
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;
const int rows=3;
const int columns=3;
[code].....