Set precision of std::to_string when converting floating point values [duplicate]

There is no way to change the precision via to_string() but the setprecision IO manipulator could be used instead:

#include <sstream>

template <typename T>
std::string to_string_with_precision(const T a_value, const int n = 6)
{
    std::ostringstream out;
    out.precision(n);
    out << std::fixed << a_value;
    return out.str();
}