Programming Forums - limiting decimal places

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aShoe

Feb 18th, 2008 6:58 PM

limiting decimal places

Can some one give me an idea of how to limit decimal spaces from a double.

dr.p	Feb 18th, 2008 8:02 PM

Re: limiting decimal places

aShoe, if you're using the iostream library for output, you need to use the setprecision() manipulator (http://cppreference.com/io_flags.html#manipulators).

Example:

#include <iostream>

#include <iomanip>

//...

float floatval = 4.026783;

std::cout << std::dec << std::setprecision(3) << floatval << std::endl;

// outputs "4.03"

Or, if you're using C style output:

#include <stdio.h>

//...

float floatval = 4.026783;

printf("%.2f\n", nfloat);

// outputs "4.03"

Ancient Dragon

Feb 18th, 2008 8:05 PM

Re: limiting decimal places

You can only limit them on output, such as with cout of another output stream

double x = 12.1234567890;

cout << setprecision(4) << width(4) << x << "\n";

has the following output

12.12

Press any key to continue . . .

[edit] I was too slow. what dr.p said[/edit]

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