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POCreating an 2D array using pointer/malloc, and then print it out
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copied!<p>I am trying to write 2 functions, one to read the matrix (2D array) and other one to print it out. So far I have:</p> <pre><code>/* Read a matrix: allocate space, read elements, return pointer. The number of rows and columns are given by the two arguments. */ double **read_matrix(int rows, int cols){ double **mat = (double **) malloc(sizeof(double *)*rows); int i=0; for(i=0; i<rows; i++){ /* Allocate array, store pointer */ mat[i] = (double *) malloc(sizeof(double)*cols); //what to do after?? return mat; } </code></pre> <p>then the print matrix function, not sure if it is correct</p> <pre><code> void print_matrix(int rows, int cols, double **mat){ for(i=0; i<rows; i++){ /* Iterate of each row */ for(j=0; j<cols; j++){ /* In each row, go over each col element */ printf("%f ",mat[i][j]); /* Print each row element */ } }} </code></pre> <p>and here is the main function I am using to run:</p> <pre><code>#include <stdio.h> #include <stdlib.h> double **read_matrix(int rows, int cols); void print_matrix(int rows, int cols, double **mat); void free_matrix(int rows, double **mat); int main(){ double **matrix; int rows, cols; /* First matrix */ printf("Matrix 1\n"); printf("Enter # of rows and cols: "); scanf("%d %d",&rows,&cols); printf("Matrix, enter %d reals: ",rows*cols); matrix = read_matrix(rows,cols); printf("Your Matrix\n"); /* Print the entered data */ print_matrix(rows,cols,matrix); free_matrix(rows, matrix); /* Free the matrix */ return 0;} </code></pre>

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