|
ceil函数的作用是求不小于给定实数的最小整数。 ceil(2)=ceil(1.2)=cei(1.5)=2.00 |
使用该函数需要包含头文件<math.h>,该函数返回值为浮点型
Run-Time Library Referenceceil, ceilfCalculates 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
);
Parameter
x
Floating-point value.
Return 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.
Input SEH Exception Matherr Exception
± QNAN,IND none _DOMAIN
ceil has an implementation that uses Streaming SIMD Extensions 2 (SSE2). See _set_SSE2_enable for information and restrictions on using the SSE2 implementation.
Remarks
C++ allows overloading, so you can call overloads of ceil. In a C program, ceil always takes and returns a double.
Requirements
Routine Required header Compatibility
ceil, ceilf <math.h> ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP
For additional compatibility information, see Compatibility in the Introduction.
Libraries
All versions of the C run-time libraries.
Example
See the example for floor.