Objective-C拓展了C,自然很多用法是和C一致的.比如浮点数转化成整数,就有以下四种情况. 1.简单粗暴,直接转化 float f = 1.5; int a; a = (int)f; NSLog("a = %d",a); 输出结果是1.(int)是强制类型转化,丢弃浮点数的小数部分. 2.高斯函数,向下取整 float f = 1.6; int a; a = floor(f); NSLog("a = %d",a); 输出结果是1.floor()方法是向下取整
用oracle sql对数字进行操作: 取上取整.向下取整.保留N位小数.四舍五入.数字格式化 取整(向下取整): select floor(5.534) from dual; select trunc(5.534) from dual; 上面两种用法都可以对数字5.534向下取整,结果为5. 如果要向上取整 ,得到结果为6,则应该用ceil select ceil(5.534) from dual; 四舍五入: SELECT round(5.534) FROM dual; ) FROM dua
在erlang的API中,erlang:trunc/1 是就近取整,erlang:round/1是四舍五入的, 整理下:对于正数的向上和向下取整, %% 向上取整 ceil(N) -> T = trunc(N), case N == T of true -> T; false -> 1 + T end. %% 向下取整 floor(X) -> T = trunc(X), case (X < T) of true -> T - 1; _ -> T end. 而对于负
向上取整 var a = 23.2325236 var abc = Math.ceil(a); //注意:Math.ceil(a)不要单独写一行,否则向上取整失败 abc = 24; 向下取整 var a = 23.2325236 var abc = Math.floor(a)//注意: Math.floor(a) 不要单独写一行,否则向下取整失败 abc = 23; 四舍五入 Math.round(7/2);