c++ round decimal to 2 places code example

Example 1: round double to n decimal places c++

float roundoff(float value, unsigned char prec)
{
  float pow_10 = pow(10.0f, (float)prec);
  return round(value * pow_10) / pow_10;
}

auto rounded = roundoff(100.123456, 3);
// rounded = 100.123;

Example 2: round double to 2 decimal places c++

double d = 0.12345;
std::cout.precision(2); // for accuracy to 2 decimal places 
std::cout << d << std::endl; // 0.12

Example 3: how to make floats output with 2 decimals c++

#include <iostream>
#include <iomanip>
using namespace std;

int main()
{
	float x=10.3445f;
	
	cout<<fixed<<setprecision(5)<<x<<endl;
	cout<<fixed<<setprecision(2)<<x<<endl;
	cout<<fixed<<setprecision(3)<<x<<endl;
	cout<<fixed<<setprecision(0)<<x<<endl;
	
	return 0;
}