ishmum-main

#include <stdio.h>
#include <math.h>
#define PI 3.141


//Used to store prototype
float MOIx(char c, float r);
float MOIy(char c, float r);


int main (void)


{

//Print the title of the results produced
printf("=========================\n");
printf("CENTROIDAL MOI CALCULATOR\n");
printf("-------------------------\n");
printf("INPUT:\n\n\n");


// Used as file pointers
char inp[50], out[50];
FILE *input;
FILE *output;


// Asking user for input file name
printf("Please enter the input file name: ");
scanf("%s", &inp);
input = fopen(inp, "r");

while (input == NULL)
{
    printf("ERROR: Input file does not exist\n");

    // prompt the user to type in the correct filename repeatedly
    printf("Please re-enter the input filename: ");
    scanf("%s", &inp);
    input = fopen(inp, "r");
}

// Asking the user for output file name
printf("Please type in the output filename: ");
scanf("%s", &out);
output = fopen(out, "w");



// Scanning and adding the file heading
char heading1[10], heading2[10];
fscanf(input, "%s %s\n", heading1, heading2);
printf("\n%s %s %s %s\n", heading1, heading2, "MOIx", "MOIy");
fprintf(output, ("\n%s %s %s %s\n", heading1, heading2, "MOIx", "MOIy"));


char ch;
float d;


// While loop is used
while(1)
{
    // Scan the radius and type
    fscanf(input, "%c ", &ch);
    fscanf(input, "%f\n", &d);

    // Print the result
    printf("%c ", ch);
    printf("%0.3e ", d);
    fprintf(output, "%c ", ch);
    fprintf(output, "%0.3e ", d);

    // Results stored for the funtions
    float value_MOIx = MOIx(ch, d);
    float value_MOIy = MOIy(ch, d);

    // Error check
    if (value_MOIx == 0 || value_MOIy == 0)
    {
        printf("INPUT ERROR\n");
        fprintf(output, "INPUT ERROR\n");
    }
    else
    {
        // Print the MOI values
        printf("%0.3e ", value_MOIx);
        printf("%0.3e\n", value_MOIy);
        fprintf(output, "%0.3e ", value_MOIx);
        fprintf(output, "%0.3e\n", value_MOIy);
    }

    if (feof(input))

    {
        break;
    }
}

}
// Formula for calculating MOI about x-axis
float MOIx(char c, float r)
{
    float result;
    if (r <= 0)
    {
        // If the radius is zero the result returned will also be zero
        result = 0;
        return result;
    }
    else
    {
        if (c == 'A')
        {
            result = (PI/4)*(pow(r, 4));
            return result;
        }
        else if (c == 'B')
        {
            result = ((PI/ 8) - (8 / (9 * PI))) * (pow(r, 4));
            return result;
        }
        else if (c == 'C')
        {
            result = 0.5 * ((PI / 8) - (8 / (9 * PI))) * (pow(r, 4));
            return result;
        }
        else
        {
            // If formula that is not defined is used the result returned will be zero
            result = 0;
            return result;
        }
    }
}


// Formula to calculate MOI about y-axis

float MOIy(char c, float r)
{
    float result;

    // If the radius is zero the result returned will also be zero
    if (r <= 0)
    {
        result = 0;
        return result;
    }
    else
    {
        if (c == 'A')
        {
         result = (PI/4)*(pow(r, 4));
         return result;
        }
        else if (c == 'B')
        {
         result = (PI/8)*(pow(r, 4));
         return result;
        }
        else if (c == 'C')
        {
         result = (PI/8)*(pow(r, 4));
         return result;
        }
        else
        {
        // If formula that is not defined is used the result returned will be zero
         result = 0;
         return result;
        }
    }
}