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


float degrees_to_radians(float degrees) {
	return M_PI * degrees / 180.0;
}


// Simple function to populate an integer array
void PopulateTheArray ( int Size, float ArrayData[])
{
    int i;      // Variable to use in our loop

    for ( i = 0 ; i < Size ; i++)
    {
        ArrayData[i] = degrees_to_radians(i); // Treat it like a normal array
    }
}
// Simple function do display contents an integer array
void DisplayTheArray ( int Size, float ArrayData[])
{
    int i;      // Variable to use in our loop

    for ( i = 0 ; i < Size ; i++)
    {
        printf ("%d\t%0.3f\n", i, ArrayData[i]);
    }
}

int SaveArray (char *filename, int Size, float ArrayData[])
{
	FILE *fp;   // File Pointer
	int i;      // Variable to use in our loop

	fp = fopen(filename, "w");
	// if file open failed, return error to caller
	if (fp == NULL) {
		return 1;
	}


	for ( i = 0 ; i < Size ; i++)
	{
		fprintf(fp, "%d\t%0.3f\n", i, ArrayData[i]);
	}

	// close file, returns 0 on successful closing (therefore function has executed sucessfully)
	return fclose(fp);
}
// Main () - execution starts here
int main (void)
{
    char filename[2049];
    int rc, iSizeForArray;
    float *pData;              // A pointer to hold the base address of out array

    // Ask for the size of the array and store result

    printf("Please enter the size of the array to dynamically allocate: ");
    scanf ("%d", &iSizeForArray);

    // Use calloc with checking
    pData = calloc( iSizeForArray, sizeof (float));

    // Check we got the memory
    if ( pData == NULL)
    {
        printf ("Sorry, I could not allocate the memory, bye!\n");
        return -1;
    }

    // Pass the size, iSizeForArray) and the pointer created 
    // which points to the start of the sucesfully allocated memory

    PopulateTheArray(iSizeForArray, pData);
    DisplayTheArray(iSizeForArray, pData);

    // Exercise doesn't ask to use function but kind of pointless without
    printf("Enter filename: ");
    scanf("%2048s", filename);
    rc = SaveArray(filename, iSizeForArray, pData);
    if (rc != 0) {
	    printf("Error saving file\n");
	    free(pData);
	    return rc;
    }

    free(pData);	    // Free up the memory before exiting
    return (0);     // Exit indicating sucess
}