使用< iomanip> ，您可以使用 std :: fixed 和 std :: setprecision

这里是一个示例

  #include< iostream> 
 #include< iomanip> 

 int main（）
 {
 double d = 122.345; 

 std :: cout<< std :: fixed; 
 std :: cout<< std :: setprecision（2）; 
 std :: cout<< d; 
} 
 

您将获得输出

  122.34 
 

I have a list of float values and I want to print them with cout with 2 decimal places.

For example:

10.900  should be printed as 10.90
1.000 should be printed as 1.00
122.345 should be printed as 122.34

How can I do this?

( setprecision doesn't seem to help in this.)

With <iomanip>, you can use std::fixed and std::setprecision

Here is an example

#include <iostream>
#include <iomanip>

int main()
{
    double d = 122.345;

    std::cout << std::fixed;
    std::cout << std::setprecision(2);
    std::cout << d;
}

And you will get output

122.34