Summary of the Floor,round and ceil of math

Floor returns the largest integer not greater than

Found is a 4-house 5-in calculation, in which is to be larger than its integer

Ceil is not less than his smallest integer

See examples

TD style= "BORDER:0;PADDING:0;" >1

 	math.flo or	math.round	math.ceil
1	1	1.5	2
1.6	2	2
-2	-1	-1
-2	-1	-1
-2	-2	-1

The test procedure is as follows:

public class MyTest {
　public static void main(String[] args) {
　　double[] nums = { 1.4, 1.5, 1.6, -1.4, -1.5, -1.6 };
　　for (double num : nums) {
　　　test(num);
　　}
　}
　private static void test(double num) {
　　System.out.println("Math.floor(" + num + ")=" + Math.floor(num));
　　System.out.println("Math.round(" + num + ")=" + Math.round(num));
　　System.out.println("Math.ceil(" + num + ")=" + Math.ceil(num));
　}
}

Run results

Math.floor(1.4)=1.0
Math.round(1.4)=1
Math.ceil(1.4)=2.0
Math.floor(1.5)=1.0
Math.round(1.5)=2
Math.ceil(1.5)=2.0
Math.floor(1.6)=1.0
Math.round(1.6)=2
Math.ceil(1.6)=2.0
Math.floor(-1.4)=-2.0
Math.round(-1.4)=-1
Math.ceil(-1.4)=-1.0
Math.floor(-1.5)=-2.0
Math.round(-1.5)=-1
Math.ceil(-1.5)=-1.0
Math.floor(-1.6)=-2.0
Math.round(-1.6)=-2
Math.ceil(-1.6)=-1.0