Setting up infile for R CMD BATCH

Ahh,
I think I'm getting it now. Well, readlines() is not going to work for
you. The help file ?readline clearly states "In non-interactive use
the result is as if the response was RETURN and the value is ?""?."
The implication is you cannot use it to "insert" different answers as
if you were really there.
How about using eval() instead? You will need to make the answers a
named list (or just assigned objects).

test <- expression({
?if(a>2) print('+')
?else print('I got more')
?b <- b+3 ? # reassign b in the environment
?print(b)
?print(c)
?d^2
})
dump('test',file='myTest.R') ; rm(test)

# make the answers.R file:

a=5 ; b=2 ; c=2 ; d=3
source("myTest.R")
eval(test)

# Now, from the terminal ?R CMD BATCH answers.R out.R
# And here is my $ cat out.R
... flushed

a=5 ; b=2 ; c=2 ; d=3
source("myTest.R")
eval(test)

[1] "+"
[1] 5
[1] 2
[1] 9

proc.time()

? user ?system elapsed
?0.640 ? 0.048 ? 0.720

Would this work?
Elai




On Tue, Feb 7, 2012 at 4:05 PM, Gang Chen <gangchen6 at gmail.com> wrote:

Suppose I create an R program called myTest.R with only one line like
the following:

type <- as.integer(readline("input type (1: type1; 2: type2)? "))

Then I'd like to run myTest.R in batch mode by constructing an input
file called answers.R with the following:

source("myTest.R")
1

When I ran the following at the terminal:

R CMD BATCH answer.R output.Rout

it failed to pick up the answer '1' from the 2nd line in answers.R as
shown inside output.Rout:

source("myTest.R")

input type (0: quit; 1: type1; 2: type2)?

1

[1] 1

What am I missing here?

Thanks in advance,
Gang