C program to Convert Binary to Float:

Steps to convert Binary to float:

1.) Separate integral and fractional part from the binary digits.

(Note : While you can separate the integral and fractional part with some algorithm, but the most convenient way to separate is, by storing the binary point number in string format or character array, so that we can compare ‘.'(binary point) easily.)
2.) Integral part can be converted to decimal by, multiplying the binary digits, starting from the LSB(Least significant bit) or from right hand side, with 2 to the power of its position(start from zero) and adding the values.

for eg : 1010 : 1*2^3 + 0*2^2 + 1*2^1 + 0*2^0

=> 1010 : 8 + 0 + 2 + 0

=> 1010 : 10

3.) To convert the fractional part to floating value, multiply the binary digits, starting from MSB(most significant bit) or left hand side of fractional number, with 2 to the power of its negative position(start from one) and adding the values.

for eg : 0.1011 : 1*2^(-1) + 0*2^(-2) + 1*2^(-3) + 1*2^(-4)

=> 0.1011 : 0.5 + 0 + 0.125 + 0.0625

=> 0.1011 : 0.6895 = > ~ 0.7

C program to convert Binary to float

‪#‎include‬<stdio.h>
#include<string.h>
#include<conio.h>

float pow(int, int);

int main()
{
char digits[50];
int befDec[50], aftDec[50];
int aftDecDigits, befDecDigits, storeIntegral=0, i, j=0, k=0;
float storeFractional=0, floatValue;
char up = 'd';

printf("******* Convert binary to float *********\n");

//Taking binary digits in character arrary
printf("Enter binary point number : ");
scanf("%s",&digits);

//Separating the integral and fractional part from the floating point value
//strlen() is an inbuilt funtion defined in string.h header file
for(i=0; i<strlen(digits); i++)
{
if(digits[i]=='.')
{
up='u';
}
else if(up=='d')
{
//ASCII value of 0 is 48, so when character is casted to integer, it results to 48, which is to be subtracted
befDec[i] = (int)digits[i]-48;
k++;
}
else
{
aftDec[j] = (int)digits[i]-48;
j++;
}
}

// Storing the lenght of Integral and fractional
befDecDigits = k;
aftDecDigits = j;

//Loop to convert the integral binary part to decimal
j=0;
for(i = befDecDigits-1; i>=0; i--)
{
storeIntegral = storeIntegral + (befDec[i] *(int) pow(2,j));
j++;
}

//Loop to convert the fractoinal binary part to floating point value
j = -1;
for(i = 0; i<aftDecDigits; i++)
{
storeFractional = storeFractional + (aftDec[i]*pow(2,j));
j--;
}

//Adding both the integral and fractional part to get the resultant value
floatValue = storeIntegral + storeFractional;
printf("Floating point value = %f\n\n\n\n\n",floatValue);
}

//Defining power function
float pow(int c, int d)
{
float pow=1;
if (d >= 0)
{
int i = 1;
while (i <= d)
{
pow = pow * c;
i++;
}
}
else
{
int i = 0;
while (i > d)
{
pow = pow/c;
i--;
}
}
return pow;
}