[英]Load R package from character string
I want to create a function which includes loading a package that I make within the function.我想创建一个 function,其中包括加载我在 function 中制作的 package。 A short example (which doesn't run:):
一个简短的示例(不运行:):
loadMe <- function(name){
genLib(xxx, libName = name) #make a new library with name "name"
library(name) #load the new library...
}
This does not work: A bit of reproducible code which illustrates my main problem:这不起作用:一些可重现的代码说明了我的主要问题:
library(ggplot) #this works fine
load.this <- "ggplot"
library(load.this) #I want this to load ggplot!
I know the problem is that library()
and require()
take as an argument an object name which does not exist yet.我知道问题在于
library()
和require()
将 object 名称作为参数,该名称尚不存在。 I have tried wrapping my character string with parse()
, deparse()
, substitute()
, expression()
, quote()
, etc etc. These all return the same problem:我尝试用
parse()
、 deparse()
、 substitute()
、 expression()
、 quote()
等包装我的字符串。这些都返回相同的问题:
library(load.this)
# Error in library(loadss) : there is no package called 'loadss'
library(deparse(load.this))
# Error in library(deparse(loadss)) : 'package' must be of length 1
Is there a way to do this?有没有办法做到这一点?
Use the character.only
argument使用
character.only
参数
foo <- "ggplot2"
library(foo,character.only=TRUE)
You say that you have tried using parse()
.您说您尝试过使用
parse()
。 The following seems to work for me:以下似乎对我有用:
eval(parse(text = 'library(MASS)')[1])
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.