fabs() in C++

The fabs() function returns the absolute value of the argument. Mathematically |a|. If a is value given in the argument. Syntax:

double fabs(double a);
float fabs(float a);
int fabs(int a);

Parameter:

• The fabs() function takes a single argument, a whose absolute value has to be returned.

Return:

• The fabs() function returns the absolute value of the argument.

Error:

• It is mandatory to give both the arguments otherwise it will give error no matching function for call to ‘fabs()’ like this.

# CODE 1

CPP

// CPP code to illustrate
// fabs() function
#include <cmath>
#include <iostream>

using namespace std;

int main()
{
    int a = -10, answer;

    answer = fabs(a);
    cout << "fabs of " << a
        << " is " << answer << endl;

    return 0;
}

OUTPUT :

fabs of -10 is 10

Time Complexity: O(1)

Space Complexity: O(1)

# CODE 2

CPP

// CPP code to illustrate
// fabs() function
#include <cmath>
#include <iostream>

using namespace std;

int main()
{
    long int a = -35;
    double answer;

    answer = fabs(a);
    cout << "fabs of " << a << " is "
        << answer << endl;

    return 0;
}

OUTPUT :

fabs of -35 is 35

Time Complexity: O(1)

Space Complexity: O(1)

Here is an example of a double.

#Code 3

C++

#include <cmath>
#include <iostream>

using namespace std;

int main() {
    double x = -3.14;
    cout << "The absolute value of " << x << " is " << fabs(x) << endl;
    return 0;
}

Output

The absolute value of -3.14 is 3.14

Time Complexity: O(1)

Space Complexity: O(1)

#Code 4

C++

#include <cmath>
#include <iostream>
#include <string>
using namespace std;

int main() {
    double x = -5.67;
    cout << "The absolute value of " << x << " is " << fabs(x) << endl;
    string s = to_string(fabs(x));
    cout<<"The absolute value of "<<x<<" is string format: "<<s<<endl;
    return 0;
}

Output

The absolute value of -5.67 is 5.67
The absolute value of -5.67 is string format: 5.670000

Time Complexity: O(1)

Space Complexity: O(1)