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Only read selected columns
Can anyone please tell me how to read only the first 6 months (7 columns) for each year of the data below, for example by using read.table() ?
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Read a file line by line assigning the value to a variable
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The following reads a file passed as an argument line by line:
while IFS= read -r line; do
echo "Text read from file: $line"
done < my_filename.txt
This is the standard form for reading lines from a file in a loop. Explanation:
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Is it safe to parse a /proc/ file?
...ommit that made it atomic. On a pre-2.6.30 kernel, you can open the file, read a bit of it, then if you later come back and read again, the piece you get will be inconsistent with the first piece. (I just demonstrated this -- try it yourself for fun.)
/proc/mounts is atomic within a single read sys...
Confused by python file mode “w+”
... a with statement like you should be. Then you'd do something like this to read from your file:
with open('somefile.txt', 'w+') as f:
# Note that f has now been truncated to 0 bytes, so you'll only
# be able to read data that you write after this point
f.write('somedata\n')
f.seek(0...
Why does SIGPIPE exist?
...hout changing global signal dispositions is to temporarily mask it with pthread_sigmask, perform the write, then perform sigtimedwait (with zero timeout) to consume any pending SIGPIPE signal (which is sent to the calling thread, not the process) before unmasking it again.
I believe the reason SIGP...
read.csv warning 'EOF within quoted string' prevents complete reading of file
I have a CSV file (24.1 MB) that I cannot fully read into my R session. When I open the file in a spreadsheet program I can see 112,544 rows. When I read it into R with read.csv I only get 56,952 rows and this warning:
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Reading a file line by line in Go
I'm unable to find file.ReadLine function in Go. I can figure out how to quickly write one, but I am just wondering if I'm overlooking something here. How does one read a file line by line?
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Is it possible to read from a InputStream with a timeout?
...tream.available():
Returns an estimate of the number of bytes that can be read (or skipped over)
from this input stream without blocking by the next invocation of a method for
this input stream.
An estimate is unavoidable due to timing/staleness. The figure can be a one-off underestimate becau...
Quickly reading very large tables as dataframes
...tables (30 million rows) that I would like to load as a dataframes in R. read.table() has a lot of convenient features, but it seems like there is a lot of logic in the implementation that would slow things down. In my case, I am assuming I know the types of the columns ahead of time, the table ...
Lazy Method for Reading Big File in Python?
I have a very big file 4GB and when I try to read it my computer hangs.
So I want to read it piece by piece and after processing each piece store the processed piece into another file and read next piece.
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