Re: [R] newbie: closing unused connection + readline
I don't understand why read.table would have a problem reading directly from a socket instead of a textConnection. Is this a bug? Some subtlety in the semantics of socketConnection as opposed to textConnection? Incorrect parameters when opening the socketConnection? No problem with socketConnection and read.table. I want to read a line at a time but when I use read.table (socketConnection) then it waits till client socket connection is closed; and entire data comes in as one big chunk. I am reading a line at a time since data will be available after every few seconds and I can process and obtain results of already generated data. Should I use some (eof) character in data so that read.table returns without client closing socket connection and I can read a line too? Thanks for your time sir(s). Regards -Aval. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] newbie: closing unused connection + readline
Hello;
I am new to R and trying to read a line from socket connection at a
time but at the end of script I am getting closing unused connection
warning. I am not able to understand how to solve this. I want to read
a line from socket and then use read.table/scan on that line but it
looks like I am opening multiple connections instead of just one. I
think I am doing something wrong or not able to understand correct
method of doing this.
---code
# Create a socket from which to read lines - one at a time (record)
reader.socket - socketConnection( host = 'localhost', 5000,
server = TRUE, blocking = TRUE,
open = r, encoding =
getOption(encoding) );
# now read each record and split/validate it using read.table
repeat {
# here for each line I am opening new connection! how to avoid it?
line.raw - textConnection(readLines( reader.socket, n = 1, ok = TRUE));
line.raw - read.table(line.raw, sep=,);
if ( length(line.raw) 1)
break;
print (showConnections());
print(warnings());
}
__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] newbie: closing unused connection + readline
Try explicitly closing it:
close(reader.socket)
or
closeAllConnections()
On Sat, May 16, 2009 at 8:34 AM, Aval Sarri aval.sa...@gmail.com wrote:
Hello;
I am new to R and trying to read a line from socket connection at a
time but at the end of script I am getting closing unused connection
warning. I am not able to understand how to solve this. I want to read
a line from socket and then use read.table/scan on that line but it
looks like I am opening multiple connections instead of just one. I
think I am doing something wrong or not able to understand correct
method of doing this.
---code
# Create a socket from which to read lines - one at a time (record)
reader.socket - socketConnection( host = 'localhost', 5000,
server = TRUE, blocking = TRUE,
open = r, encoding =
getOption(encoding) );
# now read each record and split/validate it using read.table
repeat {
# here for each line I am opening new connection! how to avoid it?
line.raw - textConnection(readLines( reader.socket, n = 1, ok = TRUE));
line.raw - read.table(line.raw, sep=,);
if ( length(line.raw) 1)
break;
print (showConnections());
print(warnings());
}
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] newbie: closing unused connection + readline
On Sat, May 16, 2009 at 6:12 PM, Gabor Grothendieck
ggrothendi...@gmail.com wrote:
Try explicitly closing it:
close(reader.socket)
or
closeAllConnections()
Thank you Sir but is there a way that it does not get open each time?
I mean following line creates a new text connection each time so how
to avoid it or reuse an open connection?
line.raw - textConnection(readLines( reader.socket, n = 1, ok = TRUE));
I tried something line this also:
mydataframe - read.table (socket, sep=,);
but does not work says no input lines.
this also.
mydataframe - read.table (readLine(socket), sep=,);
what is the best method of doing something like this? I am getting
totally lost between textConnection, socket and getConnection. Now I
am trying to get the connection that was opened and reuse it but then
how do I get connection that was previously opened when running code -
since getConnection() requires a number and for that I need to know
the number of my previously opened connection. So how do I get the
number of textConnection that I open?
Sir any pointers would greatly help.
Thanks and regards
-Aval
On Sat, May 16, 2009 at 8:34 AM, Aval Sarri aval.sa...@gmail.com wrote:
Hello;
I am new to R and trying to read a line from socket connection at a
time but at the end of script I am getting closing unused connection
warning. I am not able to understand how to solve this. I want to read
a line from socket and then use read.table/scan on that line but it
looks like I am opening multiple connections instead of just one. I
think I am doing something wrong or not able to understand correct
method of doing this.
---code
# Create a socket from which to read lines - one at a time (record)
reader.socket - socketConnection( host = 'localhost', 5000,
server = TRUE, blocking = TRUE,
open = r, encoding =
getOption(encoding) );
# now read each record and split/validate it using read.table
repeat {
# here for each line I am opening new connection! how to avoid it?
line.raw - textConnection(readLines( reader.socket, n = 1, ok = TRUE));
line.raw - read.table(line.raw, sep=,);
if ( length(line.raw) 1)
break;
print (showConnections());
print(warnings());
}
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] newbie: closing unused connection + readline
On Sat, May 16, 2009 at 8:34 AM, Aval Sarri aval.sa...@gmail.com wrote:
# Create a socket from which to read lines - one at a time (record)
reader.socket - socketConnection( host = 'localhost', 5000,
server = TRUE, blocking = TRUE,
open = r, encoding =
getOption(encoding) );
# now read each record and split/validate it using read.table
repeat {
# here for each line I am opening new connection! how to avoid it?
line.raw - textConnection(readLines( reader.socket, n = 1, ok = TRUE));
What is the function of textConnection here? Is read.table
incompatible with socketConnection for some reason?
line.raw - read.table(line.raw, sep=,);
...at the end of script I am getting closing unused connection warning
This is not a problem in itself. For some reason, R gives a warning
when connections are garbage collected. Of course, that can be a
symptom of poor connection management, but not necessarily.
In the present case, you are creating many unnecessary
textConnections, and R correctly garbage collects them.
-s
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] newbie: closing unused connection + readline
On Sat, May 16, 2009 at 9:11 AM, Aval Sarri aval.sa...@gmail.com wrote: ...I tried something line this also: mydataframe - read.table (socket, sep=,); but does not work says no input lines. this also. mydataframe - read.table (readLine(socket), sep=,); Sorry, I didn't see this before my last email. This seems to be the real problem I don't understand why read.table would have a problem reading directly from a socket instead of a textConnection. Is this a bug? Some subtlety in the semantics of socketConnection as opposed to textConnection? Incorrect parameters when opening the socketConnection? -s __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
