链接中的算术运算符 [英] Chaining arithmetic operators in dplyr

问题描述

我想了解为什么在 dplyr 或 magrittr 包中，更具体地说，链接功能％>％在基本运算符 + ， - ， * 和 /

获取以前语句的输出，并将其作为下一个语句的第一个参数提交：

  1:10％>％sum 
＃[55] 
  

因此，这是不行的

  1:10％>％* 2％>％sum 
 1:10％>％。* 2％>％sum 
  

我还发现以下语法适用于添加/减法，但不能乘法或除法。为什么这样？

  1:10％>％+（2）＃works OK 
 1:10％> ;％*（2）＃nope ... 
  

所以我应该写一个匿名的功能，一个 * 2 对我的data.frame的操作

  1:10 ％>％（function（x）x * 2）％>％sum 
  

在其他SO问题中找不到答案。

解决方案

使用反引号或引号围绕运算符，事情应按预期工作：

  1:10％>％`*`（2）％>％sum 
＃[1 ] 110 
 
 1:10％>％`/`（2）％>％sum 
＃[1] 27.5 
  pre> 
I would like to understand why, in the the dplyr or magrittr package, and more specifically the chaining function %>% has some trouble with the basic operators +, -, *, and /

Chaining takes the output of previous statement and feeds it as first argument of the next:
1:10 %>% sum
# [55]
Thus how come this doesn't work
1:10 %>%  *2 %>% sum
1:10 %>% .*2 %>% sum
I also found that the following syntax works for adding/substracting, but not multiply or divide. why so?
1:10 %>% +(2) # works OK
1:10 %>% *(2) # nope...
So should I write an anonymous function even to do a *2 operation on my data.frame?
1:10 %>% (function(x) x*2) %>% sum
Thanks, I couldn't find the answer in other SO questions.
解决方案
Surround the operators with backticks or quotes, and things should work as expected:
1:10 %>%  `*`(2) %>% sum
# [1] 110

1:10 %>%  `/`(2) %>% sum
# [1] 27.5


                        
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