Create a matrix of matrices using c ++ pointers

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Good evening. Years ago I studied C and I am currently using it but with C ++ to get into classes when it's time. Unfortunately I do not have my notes (of C) and the queries that I have put in google do not satisfy me in addition the tests that I am doing do not go so far that I no longer have a code nor even compile

My idea is feasible, I know it is because it sounds like I have done it in the past, I have a series of vectors, four vectors and suppose dimension two.

a = (a1, a2) b = (b1, b2) c = (c1, c2) d = (d1, d2)

And on the other hand I have the ability to create a 2x2 matrix

z = (z1, z2; z3, z4)

The idea is that z1 stores the memory of a in the first place, that is, z1 has the position of a, specifically of the first component.

Later, when you have that matrix full of pointers, it would do more operations.

The sketch that I leave you and have tried is: 

float a[2]={1,2};
float z[2][2];
float *puntero=NULL; //Puntero nulo
puntero=a //Apunto al vector a concretamente a la posicion 1 (0 en c/c++)
z[0][0]=&puntero //Le doy al primer componente de la matriz la direccion de memoria de puntero que es la del vector.

What am I doing wrong?

    
asked by Alvaro 24.04.2017 в 23:28
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1 answer

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Well from the moment that C ++ does not support an array of references the simplest is to resort to an array of pointers, in your case you declare an array of pointers of 4 positions and just position you assign an array of integers. 

int main()
{

    int a[]={1,2};
    int b[]={3,4};
    int c[]={5,6};
    int d[]={7,8};


    int *arrayPunteros[4]={a,b,c,d};

    //Muestra las direcciones de memoria de cada array
    cout<<a<<endl;
    cout<<b<<endl;
    cout<<c<<endl;
    cout<<d<<endl;

    //Recorremos el array para comprobar que realmente coinciden las direcciones 
    // ademas mostramos su contenido
    for(int i=0;i<4;i++){
        cout<<"Direccion de arrayPunteros["<<i+1<<"] "<<arrayPunteros[i]<<endl;
        cout<<"Valor ==> "<<arrayPunteros[i][0]<<endl;
        cout<<"Valor ==> "<<arrayPunteros[i][1]<<endl;
    }

    return 0;
}
    
answered by 24.04.2017 в 23:44
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