The Round/ceil/floorf function in iOS is slightly solved

extern float Ceilf (float);

extern double ceil (double);

extern long double Ceill (long double);


extern float Floorf (float);

extern double floor (double);

extern long double floorl (longdouble);


extern float roundf (float);

extern double round (double);

extern long double Roundl (longdouble);

The following information is from the network:

Round: If the parameter is a decimal, then the rounding of itself is asked.
Ceil: If the parameter is a decimal, the smallest integer is not less than itself.
Floor: If the parameter is a decimal, the largest integer is evaluated but not greater than itself.

Example: How the value is 3.4, then

3.4--round 3.000000

--Ceil 4.000000

-Floor 3.00000


CGRectMake (Floorf (self.view.bounds.size.width*0.5f-39.f*0.5f), self.view.bounds.size.height-57, 39, 39)

where Floorf (self.view.bounds.size.width*0.5f-39.f*0.5f) returns a value of

140.000000 this form

The Round/ceil/floorf function in iOS is slightly solved