addup
|
Some programs output information in columns.
The
addup
script totals the numbers in a column.
It reads from files or standard input.
For example,
the
lastcomm
command shows CPU time used in column 4, like this: |
%
lastcomm tcomm
sleep tcomm __ 0.08 secs Thu Mar 27 10:23
date tcomm __ 0.08 secs Thu Mar 27 10:23
tail tcomm __ 0.09 secs Thu Mar 27 10:23
pwho tcomm __ 0.30 secs Thu Mar 27 10:23
%
lastcomm tcomm | addup 4
0.550000
grep -c
(
15.8
)
outputs the number of matches after a colon (
:
) on each line.
To total the matches, pipe
grep
's output through a
little
sed
command to strip off the filenames and colon;
have
addup
sum the output (the "first column"):
%
grep -c CAUTION *.txt
abar.txt:0
applic.txt:3
badprob.txt:235
...
%
grep -c CAUTION *.txt | sed 's/.*://' | addup 1
317
Here's the script:
case "$1" in
[1-9]*) colnum="$1"; shift;;
*) echo "Usage: `basename $0` colnum [files]" 1>&2; exit 1;;
esac
# Use integer output, but switch to %.4f format if "." in input.
awk '{sum += $col}
END {print sum}' col=$colnum OFMT='%.4f' ${1+"$@"}
The
${1+"$@"}
holds filenames (if any) from the command line and
works around a
shell quoting problem (
46.7
)
.
The
awk
script passes in the column through a variable on its
command line, then
$col
becomes the column number.
The script defaults to integer output format, without a decimal point.
If it sees a "." in the input (like
1.5
),
it switches to floating-point output format; the
OFMT
variable
setting of
%.4f
forces
awk
to always print the result
with four digits after the decimal point.
(The default
OFMT
setting,
%.6g
, prints large numbers in
e-notation.
If you want that, delete the
OFMT='%.4f'
.)