Question

I am working on replicating the load() function from MATLAB for use in a C application. I am having trouble dynamically loading the data and initializing the arrays that I need. More specifically, I am trying to use fgets with arrays that have been initialized with calloc, and I cannot get it to work. The function is below, and help is appreciated.

EDIT: Updated code is below the following flawed example.

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

void *load(const char *Filename);

void *load(const char *Filename)
{
    FILE* FID;
    if ((FID = fopen(Filename, "r")) == NULL)
    {
        printf("File Unavailable.\n");
    }
    else
    {
        int widthCount = 0, heightCount = 0;

        char ReadVal;
        while ((ReadVal = fgetc(FID)) != '\n')
        {
            if (ReadVal == ' ' || ReadVal == ',' || ReadVal == '\t')
            {
                widthCount++;
            }
        }

        rewind(FID);
        char* String = calloc(widthCount * 100, sizeof(char));
        while (fgets(*String, widthCount+1, FID) != EOF)
        {
            heightCount++;
        }
        double* Array = calloc(widthCount * heightCount, sizeof(double));
        rewind(FID);
        int i = 0, j = 0;
        char * pch;
        while (fgets(*String, widthCount+1, FID) != EOF)
        {
            pch = strtok(String, " ,\t");
            while (pch != NULL)
            {
                Array[i][j] = strtod(pch, NULL);
                pch = strtok (NULL, " ,\t");
                j++;
            }
            i++;
            j = 0;
        }

        fclose(FID);
        return Array;

    }

}

The revised code: This solution works, for anyone looking at a similar problem.

void *load(const char *Filename)
{
    FILE* FID;
    if ((FID = fopen(Filename, "r")) == NULL)
    {
        printf("File Unavailable.\n");
        return NULL;
    }
    else
    {   
        int widthCount = 0, heightCount = 0;
        double *Array;
        char Temp[100];
        while ((Temp[0] = fgetc(FID)) != '\n')
        {
            if (Temp[0] == '\t' || Temp[0] == ' ' || Temp[0] == ',')
            {
                widthCount++;
            }
        }
        widthCount++;
        //printf("There are %i columns\n", widthCount);
        rewind(FID);
        while (fgets(Temp, 99, FID) != NULL)
        {
            heightCount++;
        }
        //printf("There are %i rows\n", heightCount);
        Array = (double *)calloc((widthCount * heightCount), sizeof(double));
        rewind(FID);
        int i = 0;
        while (!feof(FID))
        {

            fscanf(FID, "%lf", &*(Array + i));
            fgetc(FID);
            i++;
        }

        return Array;   
    }
}
Was it helpful?

Solution

Array isn't a 2d array instead of Array[i][j] = strtod(pch, NULL); just increment the pointer *(Array++) = strtod(pch, NULL);

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