Setting precision?

This is a discussion on Setting precision? within the C++ Programming forums, part of the General Programming Boards category; How can I set the number of decimal places when writing to an ofstream? I want to always write 2 ...

  1. #1
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    Setting precision?

    How can I set the number of decimal places when writing to an ofstream? I want to always write 2 decimal places, even if they are both zero.
    Thanks

  2. #2
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    In C I have done something like the following:

    Code:
    fprintf(parout, "-weight=%2.f", weight);
    This will print out weight with 2 decimal places, even if they are both zero. Is there a way to do this in C++?
    Thanks

  3. #3
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    use setprecision(2) with cout and include <iomanip>
    eg

    int x = 2.143234234;
    cout << setprecision(2) << x << endl;

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    Doesnt seem to work!

    The setprecision function only seems to work if the positions are non zero. Is there some other way? Say I have weight = 10, and I want it to be printed as 10.00. Is there a way to do this?
    Thanks

    The set precision function takes a value n, and this is the maximum number of decimal places, but it doesnt necessarily use them all.
    Last edited by markucd; 01-23-2006 at 04:17 AM.

  5. #5
    ZuK
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    Code:
    double x = 2.143234234;
    cout << fixed  << setprecision(2) << x << endl;
    Kurt

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    Thanks!

    That works

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