captureOutput: Evaluate an R expression and captures the output
Description
Evaluate an R expression and captures the output.Usage
captureOutput(expr, file=NULL, append=FALSE, collapse=NULL, envir=parent.frame())
Arguments
expr
The R expression to be evaluated.
file
A file name or a connection
to where the output is
directed. Alternatively, if NULL
the output is captured to
and returned as append
If TRUE
, the output is appended to the file or
the (unopened) connection, otherwise it overwrites. collapse
A character
string used for collapsing the captured
rows. If NULL
, the rows are not collapsed. Details
This method immitates capture.output
with the major
difference that it captures strings via a raw
connection rather
than via internal strings. The latter becomes exponentially slow
for large outputs [1].References
[1] R-devel thread 'capture.output(): Using a rawConnection() [linear]
instead of textConnection() [exponential]?', 2014-02-03.
https://stat.ethz.ch/pipermail/r-devel/2014-February/068349.htmlSee Also
Internally, eval
() is used to evaluate the expression.
and capture.output
to capture the output.