本文介绍了当使用<<<有双的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我需要防止我的双面以我的文件中的科学记数法打印,



当我这样做

  outfile< X; 


解决方案

要设置浮动变量的格式, , a href =http://en.cppreference.com/w/cpp/io/manip/showpoint> showpoint 和。为了使用 setprecision(n)这样的参数化流操作符,你必须包括iomanip库:

  #include< iomanip> 

setprecision(n):将限制浮动输出到 n 个地方,一旦你设置它,它被设置,直到你显式地取消它为流输出的剩余部分。



fixed :将强制所有浮点数以相同的方式输出。因此,如果您的精度设置为4个位置,则 6.2 6.20

  6.2000 
6.2000

showpoint :将强制显示浮点变量的小数部分,即使没有显式设置。例如, 4 将输出为:

  4.0 $ b $ 

  

code> outfile<<固定<显示点
outfile<< setprecision(4);
outfile<< X;


I need to prevent my double to print in scientific notation in my file,

when I do this

outfile << X;
解决方案

To set formatting of floating variables you can use a combination of setprecision(n), showpoint and fixed. In order to use parameterized stream manipulators like setprecision(n) you will have to include the iomanip library:

#include <iomanip>

setprecision(n): will constrain the floating-output to n places, and once you set it, it is set until you explicitly unset it for the remainder of the stream output.

fixed: will enforce that all floating-point numbers are output the same way. So if your precision is set to 4 places, 6.2, and 6.20 will both be output as:

6.2000
6.2000

showpoint: will force the decimal portions of a floating-point variable to be displayed, even if it is not explicitly set. For instance, 4 will be output as:

4.0

Using them all together:

outfile << fixed << showpoint;
outfile << setprecision(4);
outfile << x;

这篇关于当使用&lt;&lt;&lt;有双的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!

07-23 22:39