C++ :: Looping Through Template Objects In Map
Dec 30, 2014How to get this code working
template <typename T>
class Dummy {
// Implementation
};
template <typename T>
class SomeClass
[Code] ......
How to get this code working
template <typename T>
class Dummy {
// Implementation
};
template <typename T>
class SomeClass
[Code] ......
I designed a class template to create unique arrays. I was able to successfully input data to and output data from my array objects, irrespective of the datatype. However, I can't for the life of me fathom why my overloaded assignment operator worked perfectly well only for integer datatype and not for double/string datatypes.
Here is the class definition:
template <class dataType>
class myArray {
public:
void setArrayData();
[code]....
And here is the definition of the overloaded assignment operator:
template<class dataType>
const myArray<dataType>& myArray<dataType>::operator=(const myArray<dataType>& rightArray) {
int i;
if(this != &rightArray) {
delete [] arrayPtr;
[Code] ....
And here is my main function that tests the operations on objects of the class:
int main(){
//object declarations
myArray<double> list(5); //a single-parameter object declaration of class myArray
myArray<double> myList(2,13); //a two-parameter object declaration of class myArray
[code]....
The problem I'm having starts from where the assignment operator is being tested: for double and string datatypes, the upper input/output section works fine, but the assignment section freezes the display until the program execution is manually terminated!
I'm trying to implement a simple template array class, but when i came into the operator< i actually have to use a template :
my code is something like :
template<typename _Type, std::size_t _Size>
class array {
public :
[Code] ......
but i am having an error of shadows template param 'class _Type' is it w/ the name conflict between the array template parameter and the function template parameter ?
Error1error C2955: 'DoubleLinkedListInterface' : use of class template requires template argument listdoublelinkedlist.h10
Error2error C2244: 'DoubleLinkedList<T>::DoubleLinkedList' : unable to match function definition to an existing declaration doublelinkedlist.cpp7
Error3 .cpperror C2244: 'DoubleLinkedList<T>::~DoubleLinkedList' : unable to match function definition to an existing declaration 12
.h
#pragma once
#include "DoubleLinkedListInterface.h"
#include "Node.h"
#include <iostream>
[Code]....
I have a generic template class with another template in one of its types. Now I want to specialize one of its methods for a particular (template) class, which leads to a compile error, however.
Here is the example:
#include <stdio.h>
template<typename Type>
class Obj1 {
public:
void ID() { printf("Object 1, size = %zu
[Code] .....
GCC ends with:
:35:27: error: type/value mismatch at argument 2 in template parameter list for ‘template<class Type, template<class> class O> class Foo’
:35:27: error: expected a class template, got ‘Obj2<Type>’
What is wrong with the specialization? Can it even be achieved and how (if so)?
how I want the code to look. Only problem is it doesn't work (Line 11). I have some experience with templates but I'm not a pro.
Basically I want the "Channels<3>" to be a type that I can use to specify a Cable with similar to vector<float/int> it would be Cable<Channels<2 or 3>>.
What have I messed up with the syntax?
#include <iostream>
#include <vector>
using namespace std;
[Code].....
I have a function:
template<class Iterator, class T>
void a(Iterator, Iterator, const T&);
and I want to be able to simplify calls to 'a' with calls like
a(someIteratableContainer);
instead of having to call:
a(someIteratableContainer.begin(), someIteratableContainer.end(), valueOfTheContainersElementType);
I also want to be able to generalize the function to handle any of the standard iteratable contains: array, vector, deque, whatever.
I was under the impression I could write:
template<template<class T> class U> a(U<T>& container) {
a(container.begin(), container.end(), g(T()));
}
where 'g()' returns an object of the element type. However, the compiler is claiming, no matter how I write a call to the overload, the original template is selected and/or the overload is invalid, depending on the various ways I attempt to write said overload.
I want to write a loop to check for prime numbers. So I'm going to check only numbers ending with 1,3,7,9.
So I need a loop that will increment with 2,4,2,2 and again 2,4,2,2...
What king of loop is best, a 'for loop' or a 'while' with switches in it or something else?
Basically I need to increment three times with 2 and then with 4, three times with 2 and then with 4...
I have been trying to get this piece of code to work but it seems to be running infinitely. What i'm trying to do is that whenever the iterator points to the map element, I check whether the element is 1 or 0. If it is 0, *do something*. But if it isn't, it should not do anything and proceed to the next element in the map.
//infinite loop - not working!
for (MapType::iterator p = pwCounter.begin(); p != pwCounter.end(); ++p) {
if (p->second.second != 1) {
[Code]....
Why this program keeps looping infinitely when i run it and try to put some input...
#include <iostream>
#include <iomanip>
#include <cstring>
#include <string>
using namespace std;
struct Account {
[Code] ....
#include <iostream>
#include <iomanip>
#include <math.h>
[Code].....
I AM HAVING TROUBLE CALCULATING THE PERCENTAGE. I HAVE TO CALCULATE THE AMOUNT OF MONEY FOR 6 YEARS.
I have a class with a .h and a .cpp file. (I'm unique!) In the .cpp file, I have a loop and a nested loop. It worked fine when it wasn't in a separate file. Now, the loops will not loop and the value found at the end is some random out of the all park number because no looping took place. I am positive that the conditions and variables are set properly.
View 1 Replies View RelatedI am having a little bit of trouble with what should be a simple part in my code. For some reason it keeps looping the name part of the program and I seem to be passing over the problem in the code.
Here is the code:
#include <iostream>
#include <string>
using namespace std;
[Code]....
I want to take a starting IP on a local network, and loop through to an ending IP on a local network, pinging all the IP addresses in between. For instance, ping all IP addresses between 192.168.1.1 - 192.168.1.255 (user enters desired starting IP and ending IP in text boxes).
I have the ping functionality working, and i can make it all work with lots of messy string parsing.. but it seems sloppy to me.
I have to split the strings (start and end IP) to get the last octet, then subtract to get the range of IPs. Then loop through, adding 1 to the last octet, and converting back to a string each time.
The C# Ping class can use either a string or an IPaddress for its Send method. If I use IPAddress, I just have to convert it from the text box it originates in, but the adding 1 to the last octet in the loop is a hassle.
Anyway, I guess the only question I have is, if you had to loop through a range of IP addresses, how would YOU do it?
public Job(string ipStartIn, string ipEndIn) {
long ip1 = Convert.ToInt64(ipStartIn);
long ip2 = Convert.ToInt64(ipEndIn);
IPStart = new IPAddress(ip1);
IPEnd = new IPAddress (ip2);
this.deviceAlive = false;
[Code] ....
how to recursively modify my program. The problem I'm hacing is the the program is not looping correctly and also not printing the correct number. I've calculated the payoff correctly, also I've only been able to print the first section of R3. I can't figure out how to loop it to get R2 to stay at 2 then go to 3 after all possiblities of R2 at 2. Enventually, R1 will change to 2 then 3; 3 being the highest number earned. To be mentioned that will be three recursive function loopR1, loopR2, and loopR3 for each column.
The result of the program should look like:
R1 R2 R3
1 1 1 payoff is 1
1 1 2 .......... 1
1 1 3 .......... 1
1 2 1 .......... 1
1 2 2 .......... 1
...
...
...
3 3 2 .............. 5
this is what I have so far:
#include <stdio.h>
#include <stdlib.h>
int payOff(int r1, int r2, int r3);
void loopR3(int R3, int upto);
void loopR2(int R2, int upto);
[Code].....
My program is designed to take a reading from a glucometer and light an LED if the reading is too high or too low. I used this code:
#include <eHealth.h>
void setup(){
pinMode(13, OUTPUT); //first alert
pinMode(12, OUTPUT); //green LED
[Code]....
The glucometer stores the tests and the code just pulls the most recent one, however even if I unplug the glucometer the first if statement keeps repeating and the LED in pin 12 keeps shining. Is it the if statement itself malfunctioning, or is the Arduino storing the data it pulled and just repeatedly plugging that into the if loop?
This has been bothering me for a while now, and I finally put together an example:
#include <iostream>
#include <string>
using namespace::std;
[Code]....
In the code above, the two classes hold pointers to each other, and that's fine but it doesn't seem right since C++ prefers to pass by reference. Yes, it can still do that (see testbox and testball) but even that seems odd to me because still you need to use pointer notation for the enclosed object. Am I the only one who feels this way, and should I just get over it? Or am I missing something that would allow an object to hold a reference?
You are to create a program using nested looping. Your program is to have a menu asking the user to select which pattern to create and how many rows to use (it should accept 1 to 10 rows and keep the aspect ratio of the pattern). The patterns are 1 - Box, 2 - V, 3 - Inverted V. Note, if I select pattern 1 with 10 rows, the box will have 10 asterisks in the first row.
Okay so i came up with the box but i have been getting stuck at getting the V or inverted V.
struct stu_dat //outside main function
{
int rollno;
char name[45],
float average;
[Code] ....
No compilation problem.when executing prompt waits for inputting rollno, but, as soon as i enter a char string it keeps looping displaying the "want to enter more data?".i cant understand what is going on,as there is no compilation problem and runs good till i input the name.
I just want my program to run continuously until someone enters 0 to exit it. I tried doing while(x=1) and looping my entire block of code. Also there is a switch one is a for one is a while loop both doing the same function. I have basic error checking and whatnot.
/*This is a program that gets a user to input a starting and ending value.
The code then prints the number ie 1 and 5 would be (1,2,3,4,5) and all the squares and cubes.
There is a case statement asking weather you want to run it as a for or as a while loop.
The choices are case sensitive.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>//allows for power and cube function
int x;
int main(){
[Code] ....
Lets say for example I have the following vector:
vector<Component*> mComponents;
and a function print() inside of class Component that prints the objects name.
How do I loop/iterate through the vector to access the print function in each object.
I am working on some coursework for university at the moment, and one of the questions asks me to 'write a function that will generate the following pattern using nested looping techniques.'
Pattern:
- . . . . . . .
. - . . . . . .
. . - . . . . .
. . . - . . . .
. . . . - . . .
. . . . . - . .
. . . . . . - .
. . . . . . . -
So far I have the following code, but when I compile it I get a host of different errors.
#include <iostream>
int main() {
int A[8][8],i,j;
for(i=0;i<8;i++) {
for(j=0;j<8;j++) {
[Code] ....
How to add code tags on this?
[URL]
#include <iostream>
struct Outer {
template<typename T>
void go() {
std::cout << Test<T>::f() << std::endl;
[Code] .....
I have tried several variants on this code to no avail. Outer is in a header, along with the extern template statements, and the specializations after main are in their own cpp file. Main is in a different cpp file.
What do have to do to make this work? I cannot bring the definitions of f() into the header, and they will be different for different template parameters. Ideally, I want Test to remain a private member of Outer, though this can change if it's the only option.
I have been trying to get a hang on templates. I have the two following functions that that could be consolidated in a single template function:
void Attractor::updateFamilies(FamiliesController *_tmp, int _counter){
center.x = ofGetWidth()/2;
center.y = ofGetHeight()/3;
attractorCounter = _counter;
if(attractorCounter == 1){
[Code] .....
NotesController and FamiliesController have the same parent. The thing that I'm trying to grasp with templates is that is could something like:
template<class TYPE>
void Attractor::updateData(TYPE* *_tmp, int _counter){
center.x = ofGetWidth()/2;
center.y = ofGetHeight()/3;
attractorCounter = _counter;
[Code] ....
And then have another template function declaration for all the attractor functions where I pass the same template value as in the first one.
As you can see, I'm calling another functions inside called attractors(_tmp). I know that one way around it could be to get rid of that function and just do all the logic inside of each if statement. Is there any way to pass the same template function parameter within a template function parameter?
I have a class like this
PHP Code:
template<class X>
class A {
X m_x;
public:
X* foo();
X* bar();
//others are not related to X
};
I would like to get rid of
PHP Code: template<class X>
For class level but still use it for members. Like this
PHP Code:
class A {
X m_x;
public:
template<class X>
X* foo();
template<class X>
X* bar();
//others are not related to X
};
However, I am still stuck at
PHP Code: X m_x;
Is it possible to create a class that stores (non-const) references to some objects and enables users direct access by using range-based for loops on them?
Code: class container {
public:
void add(int& value);
void remove(int& value);
...
};
int main()
{
container c;
for (auto& value:c) {
// `value' should be accessible as type `int&' instead of being a pointer, `std::reference_wrapper<int>' or something like that
}
}