楼主: tf2000
36620 16

R的取整函数是什么? [推广有奖]

  • 2关注
  • 3粉丝

讲师

20%

还不是VIP/贵宾

-

威望
0
论坛币
2468912 个
通用积分
3.8287
学术水平
12 点
热心指数
33 点
信用等级
5 点
经验
7976 点
帖子
234
精华
0
在线时间
586 小时
注册时间
2004-12-7
最后登录
2024-6-5

+2 论坛币
k人 参与回答

经管之家送您一份

应届毕业生专属福利!

求职就业群
赵安豆老师微信:zhaoandou666

经管之家联合CDA

送您一个全额奖学金名额~ !

感谢您参与论坛问题回答

经管之家送您两个论坛币!

+2 论坛币

R的取整函数是什么?

类似于excel里的INT()函数。

谢谢!

二维码

扫码加我 拉你入群

请注明:姓名-公司-职位

以便审核进群资格,未注明则拒绝

关键词:EXCEL exce xcel cel int 函数

不要疑惑,只要信。
沙发
angelboy 在职认证  发表于 2007-12-19 08:51:00 |只看作者 |坛友微信交流群
clng()  ???
农妇 山泉 有点田

使用道具

藤椅
philzang 发表于 2007-12-19 16:28:00 |只看作者 |坛友微信交流群

可供选择的有:ceiling(), floor()

每个函数具体是取上整还是取下整可以参见R的帮助文件

已有 1 人评分经验 收起 理由
李会超 + 20 分析的有道理

总评分: 经验 + 20   查看全部评分

使用道具

板凳
tf2000 发表于 2007-12-20 10:03:00 |只看作者 |坛友微信交流群

多谢!多谢!

不要疑惑,只要信。

使用道具

报纸
hxcan 发表于 2008-12-30 14:43:00 |只看作者 |坛友微信交流群
知道了,多谢!
太极美术工程师师长。
http://stupidbeauty.com/Blog

使用道具

地板
yzharold 发表于 2009-2-7 18:51:00 |只看作者 |坛友微信交流群
ceiling()是上取
floor() 是下取

使用道具

7
coral033 在职认证  发表于 2009-2-15 22:14:00 |只看作者 |坛友微信交流群

参见R的帮助文件:help(ceiling) or help(floor)。搜索结果如下:

Rounding of Numbers

Description

ceiling takes a single numeric argument x and returns a numeric vector containing the smallest integers not less than the corresponding elements of x.

floor takes a single numeric argument x and returns a numeric vector containing the largest integers not greater than the corresponding elements of x.

trunc takes a single numeric argument x and returns a numeric vector containing the integers formed by truncating the values in x toward 0.

round rounds the values in its first argument to the specified number of decimal places (default 0).

signif rounds the values in its first argument to the specified number of significant digits.

zapsmall determines a digits argument dr for calling round(x, digits = dr) such that values close to zero (compared with the maximal absolute value) are ‘zapped’, i.e., treated as 0.

Usage

ceiling(x) floor(x) trunc(x, ...) round(x, digits = 0) signif(x, digits = 6) zapsmall(x, digits = getOption("digits")) 

Arguments

xa numeric vector. A complex vector is allowed for round, signif and zapsmall.
digitsinteger indicating the precision to be used.
...arguments to be passed to methods.

Details

All but zapsmall are generic functions: methods can be defined for them individually or via the Math group generic.

Note that for rounding off a 5, the IEC 60559 standard is expected to be used, ‘go to the even digit’. Therefore round(0.5) is 0 and round(-1.5) is -2. However, this is dependent on OS services and on representation error (since e.g. 0.15 is not represented exactly, the rounding rule applies to the represented number and not to the printed number, and so round(0.15, 1) could be either 0.1 or 0.2).

For signif the recognized values of digits are 1...22. Complex numbers are rounded to retain the specified number of digits in the larger of the components. Each element of the vector is rounded individually, unlike printing.

All except zapsmall are primitive, but as from R 2.7.0 arguments are matched by name in round and signif (whereas the default method for ceiling, floor and trunc ignore argument names).

S4 methods

ceiling, floor and trunc are S4 generic and members of the Math group generic. As an S4 generic, trunc has only one argument.

round and signif are S4 generic and members of the Math2 group generic.

References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole. (Except zapsmall.)

Chambers, J. M. (1998) Programming with Data. A Guide to the S Language. Springer. (zapsmall.)

See Also

as.integer.

Examples

round(.5 + -2:4) # IEEE rounding: -2 0 0 2 2 4 4 ( x1 <- seq(-2, 4, by = .5) ) round(x1)#-- IEEE rounding ! x1[trunc(x1) != floor(x1)] x1[round(x1) != floor(x1 + .5)] (non.int <- ceiling(x1) != floor(x1)) x2 <- pi * 100^(-1:3) round(x2, 3) signif(x2, 3) print (x2 / 1000, digits=4) zapsmall(x2 / 1000, digits=4) zapsmall(exp(1i*0:4*pi/2)) 
<script language="JScript"></script>
Out of difficulties, makes miracles.

使用道具

8
yuer1027 发表于 2009-5-8 12:42:00 |只看作者 |坛友微信交流群

我也用上了,谢谢

使用道具

9
bella501907914 发表于 2014-6-24 11:41:53 |只看作者 |坛友微信交流群
有用,谢谢~

使用道具

10
AthenaUchiha 发表于 2015-3-17 10:06:36 |只看作者 |坛友微信交流群
多谢多谢!

使用道具

您需要登录后才可以回帖 登录 | 我要注册

本版微信群
加好友,备注cda
拉您进交流群

京ICP备16021002-2号 京B2-20170662号 京公网安备 11010802022788号 论坛法律顾问:王进律师 知识产权保护声明   免责及隐私声明

GMT+8, 2024-6-5 21:55