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Possible Duplicate:
How do I print a double value with full precision using cout? 

float a = 175.;
   cout << a;

If I run the previous code I'll get just 175, how can I cout the number with (for example) 3 decimal places even they were zeros .. How can I print "175.000" ?!

Wolf
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Muhammad Barrima
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2 Answers2

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You need std::fixed and std::setprecision:

 std::cout << std::fixed << std::setprecision(3) << a;

These require following header:

#include <iomanip>
Ancurio
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Jesse Good
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    Ahh, iostreams... seamlessly combining the speediness of a turtle and the beauty of Andrew LLoyd-Webber. – Kerrek SB Feb 03 '13 at 21:42
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    For future reference, if you're outputting multiple values, you only need to pass the manipulators once: `float a = 2.5; float b = 3.5; std::cout << std::fixed << std::setprecision(3); std::cout << a << std::endl; std::cout << b << std::endl;` – Kyle Jul 11 '19 at 13:39
  • @MuhammadBarrima Please accept this answer if that's what you needed to show that this question is resolved. – ReinstateMonica3167040 Dec 07 '19 at 15:31
4

Try setprecision:

cout.setf(ios::fixed);
cout << setprecision(3) << a << endl;