C++ <cmath> - floor() Function

The C++ <cmath> floor() function returns the next lowest integer value by rounding down the specified number, if necessary. In other words, it rounds the fraction DOWN of the given number.

Syntax

C++98
C++11

double floor (double x);
float floor (float x);
long double floor (long double x);

double floor (double x);
float floor (float x);
long double floor (long double x);
//additional overloads for integral types  
double floor (T x);

Parameters

`x`	Specify a number.

Return Value

Returns the next lowest integer value by rounding DOWN the specified number, if necessary.

Example:

In the example below, floor() function is used to round the fraction DOWN of the specified number.

#include <iostream>
#include <cmath>
using namespace std;
 
int main (){
  cout<<floor(10.5)<<"\n";
  cout<<floor(-10.5)<<"\n";
  cout<<floor(0.5)<<"\n";
  cout<<floor(-0.5)<<"\n";   
  return 0;
}

The output of the above code will be:

❮ C++ <cmath> Library