Floor() Function in C

The floor() function is part of the math library (math.h). It is used to round a floating-point number down to the nearest integer value that is less than or equal to the original number. The floor() function returns a double value.

Here’s the prototype of the floor() function:

#include <math.h>

double floor(double x);

• x: The floating-point number that you want to round down.

The floor() function effectively truncates the fractional part of the floating-point number, leaving only the integer part. It always rounds towards negative infinity.

Here’s an example of how to use the floor() function:

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

int main() {
    double num = 7.9;
    double result = floor(num);

    printf("Original number: %.2f\n", num);
    printf("Floor value: %.2f\n", result);

    return 0;
}

In this example, we use the floor() function to round down the number 7.9, and the result is 7.0.

The floor() function is often used in various mathematical and numerical applications where you need to round down a floating-point value to the nearest integer value.