Say I made a vector matrix:
vector<vector<int> > matrix;
and the matrix look likes this:
0,0
0,1
0,2
...
How would I make it get a random piece of this matrix? So for example, how would I get it to access a set of variables like 1,3 like as if it was just an array with stored data in it?
Any way to use a string to access a specific item in a matrix of int[X].
I have a program which uses enums as iterators to reference a large amount of data. To select an item in the matrix, the user will enter a string, which is also an enum, which also must serve as an iterator for something in the matrix. Here is a toybox example:
#include <iostream>
#include <string>
using namespace std;
enum NyNumbers { First, Second, Third, Forth, LAST_VALUE };
int main(int argc, char* argv[]) {
int Matrix[LAST_VALUE] = { 1, 3, 7, 12 };
[Code] .....
The idea is the user executes the program by typing "./RUN First" to print out the first element in the MyNumbers array, "./RUN Second" to access the second, and so on. I can't use static numbers for the iterator. (i.e., "./RUN 1") I must reference by enum/string.
When run, the output of this problem is thus:
====================================================================
user@debian$ ./RUN Second
Matrix[ atoi(Second) ]: 1
user@debian$
====================================================================
BTW, if I change line 12 to this
====================================================================
cout<<Matrix[ argv[1] ]<<"
";
====================================================================
The error message is this
====================================================================
user@debian$ make
g++ -g -Wall -ansi -pg -D_DEBUG_ Main.cpp -o exe
Main.cpp: In function `int main(int, char**)':
Main.cpp:12: error: invalid types `int[4][char*]' for array subscript
make: *** [exe] Error 1
user@debian$
====================================================================
Which isn't unexpected. How to input the enum as argv[1]?
There is a genereted matrix of buttons:
private void Single_Load(object sender, EventArgs e) {
//code here
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
//a lot of working code here
b[i, j].Click += new System.EventHandler(ClickButton);
}
}
}
What can I do when one of those buttons is pressed (i have the method ClickButton) to know what i and j has he?
I want to make something like this
ClickButton() {
if (x%2==0)
v[i, j] = x; //i and j should be form the matrix of buttons
}
When I am giving elements for row 2 ,program crashes .it says access violation.
Code:
#include<iostream>
#include<vector>
#include<string>
using namespace std;
void matrix_init(vector<vector<string>>& v)
[Code] ....
On linux, I can compile DLLs (shared objects) as well as executables that use them. I can even access globals and classes that are defined in the EXE from the DLL, and vice versa, simply with the 'export' keyword. flawlessly.
The Problem: But on Windows (using MinGW), no matter what I do, I'm completely unable to access global variables which defined in the EXE, from the DLL. On Linux, this is no sweat, but what's Windows' problem?
I also need to extend classes in the dll with base class method definitions defined in the exe.
Ive heard that on Windows, you need to use declspec(dllimport) and declspec(dllexport). I can compile with CygWin+MinGW/g++4.5.3 as well as "Pure Windows" with MinGW/g++4.7.2 *without* the declspecs. So what's the decljunk for? Is this really just something for MSVC or other compilers?
Here's some Windows code to show what the problem is. The DLL's global variable is accessible to the EXE just fine, but the EXE's global variable is not accessible to the DLL - compilation complains it is an undefined reference.
main.cpp
#include "myLib.h"
#include <stdio.h>
int exe;
[Code].....
edit: I tried using --enable-runtime-pseudo-reloc --allow-shlib-undefined options when compiling the DLL and G++ complains that --allow-shlib-undefined is an unrecognized option.
my clsLocalStudent inherits from clsStudent. How to i set my accounts information (accountNumber, accountHolderID . . . . .)?
Code:
#include <iostream>
#include "clsInterest.h"
#include "clsDate.h"
[Code]......
Alright, so I'm making a windows form with a few hundred buttons, and one button will change color based on data the program receives over a socket. This is what I have, and it kind of works, but I don't want to have to make another if statement for all 260 buttons.
void hitmiss(std::string u){
std::string^ ind = reccdata2();
if (u == "button6"){
if (ind == "1"){
this->button6->BackColor = System::Drawing::Color::Red;
this->textBox2->Text = L"hit";
[Code] .....
What I want to do is make it more like
void hitmiss(System::String^ u){
std::string^ ind = reccdata2();
if (ind == "1"){
this->u->BackColor = System::Drawing::Color::Red;
this->textBox2->Text = L"hit";
[Code] ....
But it returns the error that u is not a part of Form1.
I am really desperate on trying to make my code work. The code is to find the eigen values of any given matrix of dimension NxN. The input can be the diagonal of any NxN matrix alongwith its subdiagonal. The code works fine for N~350 or so but when i go beyond that these errors appear.
First-chance exception at 0x00425ea4 in divide.exe: 0xC0000005: Access violation writing location 0x01141000.
Unhandled exception at 0x00425ea4 in divide.exe: 0xC0000005: Access violation writing location 0x01141000.
But as i have never declared any variable statically and when i dynamically allocating memory with variables it should work like it does for smaller N values.
I have written a class "FileSet " in program's Document class.
This class contains other Four classes as
"Machine1" , "Machine2", "Machine 3" and "Machine 4".
Now my problem is Machine 1 can not access variables from Document class or other variables from FileSet.
How to access them ?
I'm unable to access private variables belonging to the object class Date, which my overloaded >> operator is a friend of. I can't see anything in my code that would be causing this error. The .h file and the definition of the problematic overloaded operator from the implementation file are below:
#ifndef DATE_H
#define DATE_H
#include <string>
using namespace std;
class Date {
public:
// Initializes a date to the default value of January 1, 1970.
[Code] .....
The error message states that the vars (month, day, year) are declared as private in the header file and then a reference is made to the lines where I attempt to access these in the .cpp file and it reads: "in this context".
i want to know how i can solve this question? do i need to create a class or write the program codes.
View 12 Replies View RelatedI just want to know the code of the program: Write code to accept matrix as aurgument and display its multiplication matrix which return its multiplication matrix.
View 1 Replies View RelatedI want to assign a matrix to submatrix of a bigger matrix.
ublas::matrix<int> A(8,5);
ublas::matrix<int> B(2,5);
for(size_t i=0;i<A.size1();++i)
for(size_t j=0;j<A.size2();++j)
A(i,j)=i*A.size2()+j+1;
for(size_t i=0;i<B.size1();++i)
for(size_t j=0;j<B.size2();++j)
B(i,j)=i*B.size2()+j+5;
ublas::matrix_range<ublas::matrix<int> > a(A,ublas::range(0,2),ublas::range(0,5));
a=B;
and it works.
but if the matrix is compressed_matrix type, there's something with it. the error log as below:
Check failed in file boost_1_48_0/boost/numeric/ublas/detail/matrix_assign.hpp at line 1078:
detail::expression_type_check (m, cm)
terminate called after throwing an instance of 'boost::numeric::ublas::external_logic'
what(): external logic
Aborted
I'm not sure this is a bug or not.
if we don't provide the acces modifiers for base class and we need to manipulate the private data of base class in derived class. Is there anyway to acces the private data members? Here's a coding example
class A {
private :
int a;
};
class B : public class A {
public :
void displayA() { cout<<a<<endl; }
};
how i can acces the a of base class A in derived class B without acces modifiers.
I have to prepare a project. But I don t know how can I do this. Program will find a matrix P for a square matrix A such that P^-1 A P ....
View 15 Replies View Related3 3
2 1 3 2 3
1 0 2
1 2 6
First line shows row and column number
First index of the second line tells the number of non-zero entries of the first row and second index tell the column number where the non zero entry is placed
for 1st row of matrix:
non-zero entries=2
column number=1
non-zero entry=3
column number=2
non-zero entry=2
covert this in the given form
0 3 3
2 0 0
0 0 6
I have a 3x3x3 matrix with values hanging from 1 to 27.
The order is this: Code: m[0][0][0] = 1;
m[0][0][1] = 2;
m[0][0][2] = 3;
m[0][1][0] = 4;
m[0][1][1] = 5;
m[0][1][2] = 6;
.
.
.
m[1][0][0] = 10;
m[1][0][1] = 11;
m[1][0][2] = 12;
.
.
.
m[2][2][0] = 25;
m[2][2][1] = 26;
m[2][2][2] = 27;
Is there an easy way to compute the indexes given the value? For example, I know that the first index can be found by dividing the value by 9.0: Code: const int firstIndex = ceil(value / 9.0) - 1; What about the second and the third indexes? I couldn't find a pattern in the numbers, and I didn't want to iterate through the matrix (the indexes will be calculated many times).
The other option is to create arrays where the values will be indexes and the matrix indexes will be the values. I'm not sure if it is the best way though
I've a code and it works on my linux laptop; however it doesnt work on a matrix server. Im getting error Code: file.c: In function CondCheck:file.c:40:3: warning: this decimal constant is unsigned only in ISO C90 [enabled by default] The code of the programme
Code:
#include <stdio.h>
#include <string.h>
#include <math.h>
/*DECIMAL TO BINARY CONVERTER*/
int BinaryConverter (int bina)
}
[code]....
I wants to print matrix such that Consider that original matrix look like following
1 2 3
4 5 6
7 8 9
Now I want to print like following
7 8 9
4 5 6
1 2 3
we can use only two for loops.
I'm writing a function that inserts a row into a matrix and deletes the last row.
But I'm having trouble. What do I need to add to this function:
//matrix :
12 5 35 35 35 65 170
48 15 190 85 27 27 24
100 315 119 600 116 129 70
88 110 145 90 90 90 90
77 85 130 55 210 122 200
// the row :
152 152 149 155 170
// matrix after adding the previous row :
12 5 35 35 35 65 170
48 15 190 85 27 27 24
100 315 119 600 116 129 70
88 110 145 90 90 90 90
77 85 130 55 210 122 200
152 152 149 155 170
We use the pointer.
- Can I print out the irregular matrix?
Code:
#include<stdio.h>
#include<conio.h>
void main()
[Code] .....
This program on running returns an error of "ILLEGAL USE OF POINTER".
Trying to multiply to matrixes using the following algorithm,
Code:
ABrec(A,B)
n=A.rows; //n must be multiple of 2
C is a new n*n matrix.
if(n==1)
C[0][0]=A[0][0]*B[0][0];
[Code] ....
but the code doesn't work !!!
Write a c++ program to display a matrix of multiples of 4 from 1 upto 30 .....
View 1 Replies View RelatedThis is my code without malloc. I need to change the array size so there is no max size for each matrix. I must dynamically allocate space for all arrays used. So I need to use malloc to create my arrays. So I cant use int A[rows][cols].
Code:
/* This program asks the user for 2 matrices called A and B, as integers, and displays their sum, C. The max dimension of each matrix is 100. */
#include<stdio.h>
// Construct function
void construct()
{
int m, n, i, j;// Variables
int first[100][100], second[100][100], sum[100][100];// Matrices variables
[Code]...
Im having a hard time understanding/using malloc. Should first, second, and sum be single pointers or double? How do I scan the matrix correctly? And how do I add them properly? Do I have to change my for loops?
Code:
/* This program asks the user for 2 matrices called A and B, as integers, and displays their sum, C. The max dimension of each matrix is 100. */
#include <stdio.h>
#include <stdlib.h>
// Construct function
void construct()
[Code]...
Code:
#include<stdio.h> Code: #include<conio.h>
void main() {
int *a[2][2],*b[2][2],*c[2][2],i,j,k;
Printf("
ENTER a MATRIX ELEMENTS
[Code] .....