How to use function with variable in R?

Question

in R,the pdf function can save graph in c:/test:

pdf("c:/test")

I want to make a variable substitue pdf ,how can i make it run ?

str<-"pdf"
str("c:/test")

Matthew Lundberg · Accepted Answer · 2012-11-18 03:21:55Z

2

get() does this:

get(str)("c:/test")

answered Nov 18, 2012 at 3:21

Matthew Lundberg

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Comments

baptiste · Accepted Answer · 2012-11-18 08:13:13Z

2

s = "pdf" ; do.call(s, list("c:/test"))

or in two steps,

cl <- call(s, "c:/test")
eval(cl)

answered Nov 18, 2012 at 8:13

baptiste

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Sven Hohenstein · Accepted Answer · 2012-11-18 08:09:10Z

1

You can extract the function specified by the name in str with match.fun:

match.fun(str)("c:/test")

By the way: It is not a good idea to name an object str since this is the name of a basic function in R.

answered Nov 18, 2012 at 8:09

Sven Hohenstein

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