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ceil, ceilf, ceill

 

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Calculates the ceiling of a value.

Syntax

double ceil(   
   double x   
);  
float ceil(  
   float x  
);  // C++ only  
long double ceil(  
   long double x  
);  // C++ only  
float ceilf(  
   float x  
);  
long double ceill(  
   long double x  
);  

Parameters

x
Floating-point value.

Return Value

The ceil functions return a floating-point value that represents the smallest integer that is greater than or equal to x. There is no error return.

Input SEH Exception Matherr Exception
± QNAN,IND none _DOMAIN

ceil has an implementation that uses Streaming SIMD Extensions 2 (SSE2). For information and restrictions about using the SSE2 implementation, see _set_SSE2_enable.

Remarks

Because C++ allows overloading, you can call overloads of ceil. In a C program, ceil always takes and returns a double.

Requirements

Routine Required header
ceil, ceilf, ceill <math.h>

For additional compatibility information, see Compatibility.

Example

See the example for floor.

.NET Framework Equivalent

System::Math::Ceiling

See Also

Floating-Point Support
floor, floorf, floorl
fmod, fmodf
round, roundf, roundl