ceil

1.months_between(date1,date2);date1和date2相减得到相差的月份。 select months_between(to_date('2015-05-11','yyyy-MM-dd'),to_date('2015-04-11','yyyy-MM-dd')) from dual ；相差一个月。 2.ceil(date1-date2);date1-date2相减得到相差的天数 select ceil(To_date('2015-05-11 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2015-04-11 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') )from dual ；相差30天。 3.获取两时间相差的豪秒数 ceil((date1 - date2) * 24 * 60 * 60 * 1000) select ceil((To_date('2015-05-11 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2015-04-11 23:59:59' , 'yyyy-mm-dd hh24-mi-ss')) * 24 * 60 * 60 * 1000) FROM DUAL; 4.获取两时间相差的秒数 ceil((date1 -

地板函数：math.floor(4.9)=4天花板函数： math.ceil(4.1)=5四舍五入： round(4.5)=4 round(4.6)=5 来源： https://www.cnblogs.com/LoganChen/p/11992005.html

On VC++ 2008, ceil(-0.5) is returning -0.0 . Is this usual/expected behavior? What is the best practice to avoid printing a -0.0 to i/o streams. ceil in C++ comes from the C standard library. The C standard says that if a platform implements IEEE-754 arithmetic, ceil( ) behaves as though its argument were rounded to integral according to the IEEE-754 roundTowardPositive rounding attribute. The IEEE-754 standard says (clause 6.3): the sign of the result of conversions, the quantize operation, the roundToIntegral operations, and the roundToIntegralExact is the sign of the first or only operand.

方法一：检查余数 以后还是养成用这种方法的习惯吧，因为他一般不会出错 if (temp%k == 0) result = temp / k ; else result = (temp / k)+1; 方法二：增加一点小处理（推荐，但可能溢出） result = (temp +k-1)/ k; 这个可以自己举个例子试试就明白了 方法三：使用cmath头文件中ceil函数（不推荐，可能会出错） result = (int)ceil(temp / k); 最大的问题： Math.ceil的返回类型是double 精度丢失可能仅仅在很极端的场景下出现，可一旦出现就是非常难以排查的隐式bug。 举个例子： 假设某两个数的ceil计算结果原本是2.0，但由于精度问题，ceil结果其实是1.9999999999999999999999999 在结果转为int型数据时，发生了精度丢失，计算结果由2.0转换为1 在任何可能出现与浮点型数据进行比较，或浮点型与整型的类型转换都必须非常注意。 参考链接：https://www.jianshu.com/p/29ce2fb998b4 来源： https://www.cnblogs.com/zlszls3113373723/p/11918001.html

When we have an array with indexes from 0 to n for example. when I use the Binary search using floor or ceiling when calculating the middle index I get the same out put. int middle = ceiling ((left+right)/2); Is there a reason using floor over ceiling ? what bug will happen using the ceiling ? There's no difference in complexity. Both variants are log(n). Depending on the rest of your implementation, you may get a different result if your array looks for instance like 0 1 1 1 1 2 and looking for the index of a 1 . This all depends on how you update your left and right variable. Normally, we

I used VLOOKUP function to find a value in an array but some of the values gave #N/A answer despite of available in array. To round up the numbers, I used CEILING function but interesting point is in some values, it did not work. I checked the type of value if it is number or not. Also, I used ROUNDUP function but did not work. Also, I tried INDEX / MATCH combination and again did not work. In the example that I gave in the link, when I type between 15.00 - 15.20, it gives error but trying other values, it works. How do I fix this? This seems to be a bug with VLOOKUP and MATCH using the return