C++ 设置double精度

设置double精度

在这里插入代码片

#include <iomanip>
#include <sstream>
int main()
{
	double mDouble = 3.14159269482786273648;
	cout<<fixed<<setprecision(3)<<mDouble <<endl;
	return 0;
}


double StrToD(string str)
{

	double tempD= atof(str);
	std::stringstream ss;
	ss << std::setiosflags(std::ios::fixed) << std::setprecision(3) << tempD;
	return tempD;
}
string DoubleToStringByStringStream(double value)
{
	std::ostringstream stream;
	stream << value;
	return stream.str();
}