Ceil is an abbreviation of the English word ceiling, and the meaning of the word isceilingsSo, without going into that yet, agile minds should be aware that the functions provided by the ceil function are the opposite of those provided by the floor function. That's right, the function provided by the ceil function, that isRound up, go to the downward rounding provided by the floor function in reverse.
In C, the ceil function is also declared and defined in mathH, for those who are experiencing how to implement common mathematical calculations in a C program, Mathh Libraries must be kept in mind. Then again, the prototype of the ceil function isdouble ceil(double x)，The parameter x can be either a number to be rounded or a simple divider.
In order to verify that the result returned by a ceil function is correct, it is necessary to understand what mathematical rounding up looks like. In mathematics, the so-called rounding up is to take the smallest integer greater than itself for a number with a decimal place, for example, given a number is , then rounding up is 4
Introducing the library is already a matter that does not need to be explained. An example of the basic usage of the ceil function is as follows:
What if the data passed into the ceil function is itself an integer? Of course, the result is the same as the original number. If you don't believe it, you can practice it yourself.