VSMechatronics/Exercises/C20/ex1.c

// Modified from C18 Ex5
#include <stdio.h>
#include <math.h>
#include <stdlib.h>

#define DEBUG_MAIN
#define DEBUG_FNS


float degrees_to_radians(float degrees) {
#ifdef DEBUG_FNS
	printf("degrees_to_radians(degrees=%f): called\n", degrees);
#endif
	return M_PI * degrees / 180.0;
}


// Simple function to populate an integer array
void PopulateTheArray ( int Size, float ArrayData[])
{
#ifdef DEBUG_FNS
	printf("PopulateTheArray(Size=%d, ArrayData): called\n", Size);
#endif
    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[])
{
#ifdef DEBUG_FNS
	printf("DisplayTheArray(Size=%d, ArrayData): called\n", Size);
#endif
    int i;      // Variable to use in our loop

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

int SaveArrayBinary (char *filename, int Size, float ArrayData[])
{
#ifdef DEBUG_FNS
	printf("DisplayTheArray(filename=%s, Size=%d, ArrayData): called\n", filename, Size);
#endif
	FILE *fp;   // File Pointer
	int i;      // Variable to use in our loop

	fp = fopen(filename, "wb");
#ifdef DEBUG_FNS
	printf("DisplayTheArray(): fp=%p\n", fp);
#endif
	// if file open failed, return error to caller
	if (fp == NULL) {
		return 1;
	}

	// write data
	fwrite(ArrayData, sizeof(float), Size, fp);
	// close file, returns 0 on successful closing (therefore function has executed sucessfully)
	return fclose(fp);
}
// Main () - execution starts here
int main (void)
{
#ifdef DEBUG_MAIN
	printf("main(): called\n");
#endif
	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);
#ifdef DEBUG_MAIN
	printf("main(): iSizeForArray=%d\n", iSizeForArray);
#endif

	// Use calloc with checking
	pData = calloc( iSizeForArray, sizeof (float));
#ifdef DEBUG_MAIN
	printf("main(): pData=%p\n", pData);
#endif

	// 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);
#ifdef DEBUG_MAIN
	printf("main(): filename=%s\n", filename);
#endif
	rc = SaveArrayBinary(filename, iSizeForArray, pData);
#ifdef DEBUG_MAIN
	printf("main(): rc=%d\n", rc);
#endif
	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
}