I am currently trying to pass a matrix (multidimensional array) from my main into a function in a class. As usual, you have to include all array sizes, except the first. Unfortunately, the size saved under a variable. When I write it in the square brackets, it doesn't work.
Example:
//main
int main () {
int n = 5;
random object;
object.declare_variable(n);
int array [3][n];
object.pass_matrix(array);
[code].....
I also tried, putting the variable 'var' in the public section above the void and declaring it as static, but still there are error messages; fewer, in my case:
...not an integer constant
So what should I do? Id like to repeat that the int n will vary, which is why I can't just directly write down the size.
how would I pass this parameter and how/why is it not working this way? I've tried many different methods to this and I can't quite seem to figure it out.
class student { public: int id; //student ID number string name; //student’s name string university; //student’ university }; //student list is a doubly linked list of students.
[code]....
My header file.
I am honestly not sure where to start here. I would assume that it would know what to do with the varibles but it doesn't seem to want to accept them. It gives me
Error1error C2660: 'studentList::push' : function does not take 3 arguments
2IntelliSense: no suitable constructor exists to convert from "int" to "student"
I make a class (it stands for an ARMA time series), and I have a method wich modifies some of its variables. In other part of my program I have a function wich receives one object of this class as a parameter and, at some point, it calls the method of the ARMA class to modify it; here is my deal I want to pass the ARMA class by reference to this function, because I want the variables of the instance I'm passing to be modified, not those of a copy the method uses. Also, I would like not to declare the function inside the class ARMA, cause I use it in other places too (it's basically a Nelder-Mead optimization what it performs).
Here is a code wich sketches what I've been trying, and exactly the error message I get is "modifyParameter has not been declared".
#include <iostream> #include <cstdlib> using namespace std; class ARMA{
How do I prevent user passing a class or a structure or aanoter function to my function print. I mean i know if a wrong thing is passed that i'll get an error eventually but is there a way to explicitly check what has been passed. How is this done usually ?
I have an array of (Student)classes created in Manager.h, which contains a new instance of class Name (name),(in Student.h)How would I go about accessing the SetFirstName method in Name.cpp if I was in a class Manager.cpp? I have tried using Students[i].name.SetFirstName("name");
// In Manager.h #include"Student.h" class Manager {
I haven't found anything that small for Matrix multiplication i was just going to ask about how i would multiply to matrices together in c++ as easy as possible, so for example say a i have the following
[2 0 1 0 * [3 0 6 -1 0 2] 0 3 1 2 3 1]
How would i multiply these together. Here is the example
I tried writing a cofactoring routine for n x n matrices and my code works but it shouldn't. Like, at all. But it does. Idk how and it's consistent.
Basically, my error is when assigning the sub-matrix for the cofactorization method I'm using from here :
Mathwords: Cofactor Matrix
My assignment routine should not work for the sub-matrix because of how I address the rows. under is always 0 and yet it'll assign values to the proper row. Idk how, it's magic.
Code: #include <stdio.h> #include <stdlib.h> long double det(long double **x, int rank) { /* Determinant calculator routine */ /* We initialize the resulting determinant to zero */
The program below should add two matrices using function. I have problem in the third function (the summing function). It's saying that something wrong with the array! I'm new to arrays and functions.
#include<iostream> #include<fstream> #include<conio.h> using namespace std; int matrix1 (); int matrix1 (); int add ();
Two different matrices will be read from text files (input1.txt, input2.txt) and they will be stored in two dimensional arrays (matrix1, matrix2) and one dimensional arrays (array1, array2). Our aim is to obtain the matrix multiplication using two dimensional and one dimensional arrays.
You are asked to write the main and the following functions. The definitions of the functions are given in the skeleton code.
int read_file(ifstream& in_file, int &row, int &col, double *array, double **matrix) int write_file(ofstream& out_file, int row, int col, double **matrix) void print_matrix(double **matrix, int row, int col) void print_array(double *array, int row, int col) void multip(double **matrix1, double **matrix2, double **result, int k, int m, int n) void multip_array(double *array1, double *array2, double *array_result, int k, int m, int n)
You are going to obtain the input and output files as command line arguments
input1.txt : 3 4 2 3 4 5 1 3 5 4 0 4 4 7
The first element in the first line represents the number of rows (3) and the second element represents the number of columns (4) of the matrix (the result file will have the same format).
thats my homework and here is the code i wrote from the sceleton code they gave me :
#include <iostream> #include <fstream> #include <string> using namespace std; int read_file(ifstream& in_file, int &row, int &col,/* double *array,*/ double **matrix)
[Code] ....
I didn't understand the array part but even when i exclude the array part i get the program has stopped working message. My os is windows7 ultimate with mingw installed and i compile the program using g++ command in cmd with the arguments input.txt input2.txt resultt.txt
I'm taking a programming class and currently we're doing data structures. Today, we discussed how to save square matrices column-wise with data structures. The teacher said that after the first few steps where you declare the structure, allocate the matrix, free it and get the dimension (which mostly make sense to me I think), you have to "get" and "set" the matrix by putting in something like
Code: void setMatrixEntry(Matrix* A, int i, int j, double Aij) { A->entries[i+j*A->m] = Aij; }
I would like to program a simple finite element solver in c++ (I'm a relatively new programmer by the way). This is the issue, I have a text file with all the information of the model arranged in matrices; an input file would look something like this:
I would like to create N matrices of dimension (n,k) simultaneously. Lets say for example that N=3. I read the command a[n][k][N] but I don't understand how to use it.
I know that for some of you this question is silly but I' m new to this language and I have noone else to ask.
The program adds 2 matrices that are 3x3 using arrays and then stores them into another matrix (array) and then it's edited to show a diagonal line of "0" through it, btw I'm pretty new to programming....
insert Code: #include <iostream> using namespace std; int main() { int x[3][3],y[3][3],c[3][3],i,j; cout<<"Enter your numbers"<<endl;
[Code] .....
It works almost just fine lol, Except that the first portion of the diagonal line does not become zero and instead displays the normal addition result.....
I've been assigned to build a program which completes mathematical operations using matrices. I have to use dynamically allocated 2d arrays, and can only use * to dereference and not []. I have this code so far, but the multiply_matrix function does not work with most values. I've looked at other similar posts, which have a similar algorithm to mine, but mine does not work for some reason.
/* *(*matrix(matrix+i)+j) */
#include <iostream> //for sleep() which allows user to see messages before screen is cleared #include <unistd.h> using namespace std;
I am unable to input the correct form for matrices multiplication. I have an exam tomorrow in which I need to use this.
Code:
#include <stdio.h> #include <conio.h> int main() { float a[10][10], b[10][10], c[10][10]; int i, j, k, l, n=0, m=0, x=0, y=0, sum=0; printf("Enter the number of rows and collumns of the first matrix"); scanf("%d %d", &n, &m);
I am trying to perform columnSum and rowSum, as well as twoDadd and twoDSubtract using the arrays defined in my driver. How would I do that using A and B in my driver?
I am working on a number of utility functions for two dimensional arrays of integers, or matrices. However I am having a problem with segmentation faults, most likely due to errors in using malloc in functions like copyMatrix.
Code: matrix_utils.h~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //This function checks if two matrices are equal int isEqual(int **A, int **B, int n);
//This function returns one row of a matrix int * getRow(int **A, int i, int n);
//This function returns one column of a matrix int * getCol(int **A, int j, int n);
I am using the gnu glpk library to calculate a linear program for my matrices. Why I get the error message exit code 3 which apparently means "The system cannot find the path specified"?
