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ceil, ceilf

Calculates the ceiling of a value.

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


Floating-point value.

The ceil function returns a double value representing the smallest integer that is greater than or equal to x. There is no error return.


SEH Exception

Matherr Exception




ceil has an implementation that uses Streaming SIMD Extensions 2 (SSE2). See _set_SSE2_enable for information and restrictions on using the SSE2 implementation.

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


Required header

ceil, ceilf


For additional compatibility information, see Compatibility in the Introduction.

See the example for floor.