scanf - using fscanf in C with varying width files -

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i need write program reads in various files , stores information arrays. using doubles perform matrix multiplies. regarding format of files; first line contains size of matrix. next several lines rows of matrix, each element separated space.

format:

<number of rows> <number of columns> <double> <double> ... <double> <double> <double> ... <double> . . . <double> <double> ... <double>

here couple example files:

3 4 1.20 2.10 4.30 2.10 3.30 3.10 5.20 2.80 1.10 0.60 4.70 4.90

or

5 5 1.20 2.10 4.30 2.10 6.70 3.30 3.10 5.20 2.80 3.20 1.10 0.60 4.70 4.90 9.10 3.30 3.10 5.20 2.80 3.20 1.10 0.60 4.70 4.90 7.10

at moment code follows:

float** readfile(char* fp) {     float** matrix = (float**)malloc(m*n*sizeof(float));      fp = fopen(fp, "r");      if (fp == null)     {         fprintf(stderr, "can't open file\n");         exit(1)     }      int = 0;     int m, n;     fscanf(fp, "%d %d", m, n);     while (fscanf(fp, "");     {         i++;     }      fclose(fp);      return matrix; }

and calling function this:

float** = readfile(argv[1]);

obviously won't work @ moment because of missing arguments in fscanf while reading file. how can use fscanf read values matrix?

to things, let use 1 dimensional array. here working code you.

#include <stdio.h> #include <stdlib.h>  float* readfile(char* fp, int *m, int *n)/* return dimension defined in file*/ {      file *file = fopen(fp, "r");      if (file == null)     {         fprintf(stderr, "can't open file\n");                 exit(1);     }      int = 0, j = 0;     fscanf(file, "%d %d[^\n]\n", m, n);     float* matrix = (float*)malloc((*m)*(*n)*sizeof(float));      float f;     (i = 0; < *m ; ++i)     (j = 0; j < *n ; ++j)     {        fscanf(file, "%f", (matrix + * (*n) + j));     }       fclose(file);      return matrix; }  int main() {     int m, n, i, j;     float *a = readfile("a.dat", &m, &n); /* named data file a.dat*/      (i = 0; < m ; ++i)         {                 (j = 0; j < n ; ++j)                    printf("%f ", *(a + * n + j));                  printf("\n");         }          free(a); }       /* output */ 1.200000 2.100000 4.300000 2.100000 6.700000 3.300000 3.100000 5.200000 2.800000 3.200000 1.100000 0.600000 4.700000 4.900000 9.100000 3.300000 3.100000 5.200000 2.800000 3.200000 1.100000 0.600000 4.700000 4.900000 7.100000

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