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Loop for fraction matrix

mermaidly (14)
Hey. How do I modify these codes:

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 void generateMatrix(vector <vector<double> > &m){

    cout << "Introduce the values of the matrix by rows and columns: " << endl;

    for (int i = 0; i < m.size(); i++)
        for (int j = 0; j < m[0].size(); j++){
            cout << "Introduce the value of the row " << i << " and column " << j << " : ";
            cin >> m[i][j];
        }

}


Into a loop that asks for each numerator and denominator by rows and columns, USING Struct "tpFraction".
I'm working with my codes below:

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void generateMatrix ( vector < vector < tpFraction > > & m ){
    int num1, num2, den1, den2, i, j;
    cout << "Introduce the values of the matrix by rows and columns: " << endl;
    for (num1 = 0; num1 < m.size(); num1++)
    for (den1 = 0; den1 < m.size(); den1++)
        for (int num2 = 0; num2 < m[0].size(); num2++)
        for (int den2 = 0; den2 < m[0].size(); den2++){
            cout << "Introduce the value of the row " << num1 << "/" << den1 << " and column " << num2 << "/" << den2 << " : ";
            
            cin >> m[i][j];

}
}


Thanks in advance.
AbstractionAnon (6954)
You haven't shown the declaration of tpFraction.

Line 10: i and j are uninitialized variables.

Line 10: Since you say that tpFraction is a struct, I would assume that it does not overload the >> operator, therefore cin does not know how to input a tpFraction.

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#include <vector>
#include <iostream>
using namespace std;
struct tpFraction
{	double	num;
	double	den;
};
void generateMatrix(vector < vector < tpFraction > > & m) 
{	int i, j;
	cout << "Introduce the values of the matrix by rows and columns: " << endl;
	for (i = 0; i < m.size(); i++)
		for (j = 0; j < m.size(); j++)
		{	cout << "Enter the numerator for row " << i << " and column " << j << " : ";
			cin >> m[i][j].num;
			cout << "Enter the denominator for row " << i << " and column " << j << " : ";
			cin >> m[i][j].den;
		}
}



mermaidly (14)
I will be modifying the codes below for tpFraction:

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void displayMatriz ( vector < vector < tpFraction > > & m ){
    struct tpFraction {
        cout << (m)[][] << "\t" ;
};
}
Last edited on
AbstractionAnon (6954)
That makes no sense.
mermaidly (14)
Here is an example of another coding work but they're in Spanish.

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#include <iostream>
#include <vector>

using namespace std;

const int kMAXDIM = 3;


void leeMatriz(vector <vector<double> > &m){

    cout << "Introduce los valores de la matriz ordenados por fila y columna: " << endl;

    for (int i = 0; i < m.size(); i++)
        for (int j = 0; j < m[0].size(); j++){
            cout << "Introduce el valor de la fila " << i << " y columna " << j << " : ";
            cin >> m[i][j];
        }

}

void escribeMatriz(vector <vector<double> > &m){

    for (int i = 0; i < m.size(); i++){
        for (int j = 0; j < m[0].size(); j++)
            cout << m[i][j] << "\t" ; // añade un tabulador tras cada valor, para mejorar la visualización
        cout << endl;
    }
    cout << endl;
}


vector<vector<double> > sumaMatrices(vector<vector<double> > &m1, vector<vector<double> > &m2){

    vector<vector<double> > resultado(m1.size(),vector<double>(m1[0].size()));

    for (int i = 0; i < resultado.size(); i++)
        for (int j = 0; j < resultado[0].size(); j++)
            resultado[i][j] = m1[i][j] + m2[i][j];

    return resultado;
}

vector<vector<double> > realxMatriz(double num, vector<vector<double> > &m){

    vector<vector<double> > resultado(m.size(),vector<double>(m[0].size()));

    for (int i = 0; i < resultado.size(); i++)
        for (int j = 0; j < resultado[0].size(); j++)
            resultado[i][j] = m[i][j] * num;

    return resultado;
}

// Función que multiplica m1 por m2 y devuelve la matriz multiplicación
// vector<vector<double> > multiplicaMatrices(vector<vector<double> > &m1, vector<vector<double> > &m2)

void transpuesta (vector<vector<double> > &m){
    vector<vector<double> > nueva(m[0].size(),vector<double>(m.size(),0.0));

    for ( int i = 0 ; i < m.size() ; i++ )
        for ( int j = 0 ; j < m[0].size() ; j++ )
            nueva[j][i] = m[i][j];

    m = nueva;
}


char muestraMenu(){

    char opcion;

    do{
        cout << "CALCULADORA DE MATRICES - MENU" << endl << endl;
        cout << "1. Transpone matriz" << endl;
        cout << "2. Calcula determinante de matriz" << endl;
        cout << "3. Multiplica matriz por real" << endl;
        cout << "4. Suma dos matrices" << endl;
        cout << "5. Multiplica dos matrices" << endl;
        cout << "0. Salir" << endl << endl;
        cin >> opcion;
    } while (opcion < '0' || opcion > '5');

    return opcion;
}


int main(){

    vector <vector<double> > m1(kMAXDIM,vector<double> (kMAXDIM)),
                             m2(kMAXDIM,vector<double> (kMAXDIM)),
                             result(kMAXDIM,vector<double> (kMAXDIM));

    char opcionMenu;
    double escalar;

    do{
        opcionMenu = muestraMenu();

        switch (opcionMenu){

            case '0':
                cout << "Hasta luego" << endl;
                break;
            case '1':
                leeMatriz(m1);
                cout << "Matriz inicial: " << endl;
                escribeMatriz(m1);
                transpuesta(m1);
                cout << "Matriz transpuesta " << endl;
                escribeMatriz(m1);
                break;
            case '2':
                // COMPLETAR
                break;
            case '3':
                leeMatriz(m1);
                cout << "Matriz inicial: " << endl;
                escribeMatriz(m1);
                cout << "Introduce escalar: " ;
                cin >> escalar;
                result = realxMatriz(escalar, m1);
                cout << "Resultado: " << endl;
                escribeMatriz(result);
                break;
            case '4':
                cout << "Matriz m1: " << endl;
                leeMatriz(m1);
                cout << "Matriz m2: " << endl;
                leeMatriz(m2);
                result = sumaMatrices(m1, m2);
                cout << "m1 + m2 = " << endl;
                escribeMatriz(result);
                break;
            case '5':
                // COMPLETAR
                break;
        }

    } while (opcionMenu != '0');


    return 0;
}


I'm referring to "void leeMatriz" and "void escribeMatriz"
George P (5600)
dhayden (5795)
You can port leeMatriz and escribeMatriz if you create << and >> operators for tpFraction. The examples below are untested.
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istream & operator >>(istream &is, tpFraction &frac)
{
    char ch;
    is >> frac.num >> ch >> frac.denom;
    if (ch != '/') {
        is.setstate(std::ios::failbit);
    }
    return is;
}

ostream &operator << (ostream &os, tpFraction &frac)
{
    return os << frac.num << " / " << frac.denom;
}

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