Floating Point Issues

What will be the output of the program?

#include<stdio.h>
int main()
{
    float a=0.7;
    if(a < 0.7)
        printf("C\n");
    else
        printf("C++\n");
    return 0;
}

A:

C

B:

C++

C:

Compiler error

D:

Non of above

Answer: A

if(a < 0.7) here a is a float variable and 0.7 is a double constant. The float variable a is less than double constant 0.7. Hence the if condition is satisfied and it prints 'C'
Example:

#include<stdio.h>
int main()
{
    float a=0.7;
    printf("%.10f %.10f\n",0.7, a);
    return 0;
}

Output:
0.7000000000 0.6999999881

📖

Which of the following statement obtains the remainder on dividing 5.5 by 1.3 ?

A:

rem = (5.5 % 1.3)

B:

rem = modf(5.5, 1.3)

C:

rem = fmod(5.5, 1.3)

D:

Error: we can't divide

Answer: C

fmod(x,y) - Calculates x modulo y, the remainder of x/y.
This function is the same as the modulus operator. But fmod() performs floating point divisions.

Example:


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

int main ()
{
  printf ("fmod of 5.5 by 1.3 is %lf\n", fmod (5.5, 1.3) );
  return 0;
}

Output:
fmod of 5.5 by 1.3 is 0.300000

📖

What will you do to treat the constant 3.14 as a float?

A:

use float(3.14f)

B:

use 3.14f

C:

use f(3.14)

D:

use (f)(3.14)

Answer: B

Given 3.14 is a double constant.
To specify 3.14 as float, we have to add f to the 3.14. (i.e 3.14f)

📖

A float occupies 4 bytes. If the hexadecimal equivalent of these 4 bytes are A, B, C and D, then when this float is stored in memory in which of the following order do these bytes gets stored?

A:

ABCD

B:

DCBA

C:

0xABCD

D:

Depends on big endian or little endian architecture

Answer: D

No answer description is available. Let's discuss.

📖

The binary equivalent of 5.375 is

A:

101.101110111

B:

101.011

C:

101011

D:

None of above

Answer: B

No answer description is available. Let's discuss.

📖

Questions for: Floating Point Issues