How to not to terminate read.table if the input file is

?try

df <- try(read.table(...))
if (inherits(df, 'try-error')){? what to do if file empty }
For the case of using try, it is better to use inherits() rather than
class(), or it doesn't matter?
On Fri, Jan 1, 2010 at 3:55 PM, Ted Harding <Ted.Harding at manchester.ac.uk>
wrote:
On 01-Jan-10 20:41:52, Peng Yu wrote:
read.table terminates the program if the input file is empty. Is there
way to let the program continue and return me a NULL instead of
terminating the program?

$ Rscript read_empty.R
read.table("empty_data.txt")
Error in read.table("empty_data.txt") : no lines available in input
Execution halted
$ cat read_empty.R
read.table("empty_data.txt")
$ cat empty_data.txt; echo EOF
EOF
If I understand the point of your query correctly, the following,
from "?read.table", would be relevant:

Value:
?A data frame (?data.frame?) containing a representation of the
?data in the file.

?Empty input is an error unless "col.names" is specified, when a
?0-row data frame is returned: similarly giving just a header line
?if "header = TRUE" results in a 0-row data frame. ?Note that in
?either case the columns will logical unless ?colClasses? was
?supplied.

The result would not be NULL, but can be tested for zero rows.

Hoping this helps,
Ted.

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Date: 01-Jan-10 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Time: 20:55:35
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What is the problem that you are trying to solve?

How to not to terminate read.table if the input file is

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