std::ceil

 

C++

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has_single_bit (C++20)     bit_cast (C++20) bit_ceil (C++20) bit_floor (C++20) bit_width (C++20) rotl (C++20) rotr (C++20)	popcount (C++20) countl_zero (C++20) countl_one (C++20) countr_zero (C++20) countr_one (C++20) byteswap (C++23) endian (C++20)

 

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abs(int)labsllabsimaxabs (C++11)   abs(float)fabs divldivlldivimaxdiv (C++11)	fmod remainder (C++11)   remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nannanfnanl (C++11)(C++11)(C++11)
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Defined in header <cmath>

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float       ceil( float arg );

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double      ceil( double arg );

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long double ceil( long double arg );

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double      ceil( Integral arg );

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<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end

Computes nearest integer not less than arg.

Parameters

arg

-

floating point value

Return value

Nearest integer not less than arg

Return value

Argument

Notes

If the argument is infinity (positive or negative) or zero (positive or negative), the return value is the same as the argument.

The largest representable floating-point values are exact integers in all standard floating-point formats, so this function never overflows.

This function may, but is not required to, raise FE_INEXACT floating-point exceptions for non-integer arguments.

Example

Run this code

#include <cmath>
#include <iostream>
 
int main()
{
    std::cout << std::fixed;
    std::cout << std::ceil(12.0) << '\n';
    std::cout << std::ceil(12.1) << '\n';
    std::cout << std::ceil(12.5) << '\n';
    std::cout << std::ceil(12.9) << '\n';
    std::cout << std::ceil(13.0) << '\n';
}

Output:

12.000000
13.000000
13.000000
13.000000
13.000000

See also

Template:cpp/numeric/math/dcl list floorTemplate:cpp/numeric/math/dcl list truncTemplate:cpp/numeric/math/dcl list roundTemplate:cpp/numeric/math/dcl list rintTemplate:cpp/numeric/math/dcl list nearbyint