Replace character in files of entire folder? sed? or what?

Shell Programming and Scripting
1

Hello,
I do have several files in one folder each file contains measurement data.
for each file I would like to replace the character "," by "." ?

How can I do this and how can I do this for each file at once?
E.G. data_1.dat, data_x.dat (original version)
data_1out.dat, data_x_out.dat (manipulated version)!

regards
rolli

2

Sorry.. You want to change the filenames? or the data inside the file?

3

To change the data inside the files:

cd /tmp/xxx
for infile in data_?.dat; do
  prefix=`basename $infile .dat`
  outfile=${prefix}_out.dat
  tr "," "." < $infile > $outfile
done
4

I would like to do this :

tr "," "." < 010_DSB_DIR_187_5Hz_MODE3_1m_hor_1.dat > 010_DSB_DIR_187_5Hz_MODE3_1m_hor_1_out.dat

for all the files in the folder at once!

using your proposal:

cd /tmp/xxx for infile in data_?.dat; do   prefix=`basename $infile .dat`   outfile=${prefix}_out.dat   tr "," "." < $infile > $outfile done

doesn't work
it cannot handle theses infile outfile environment variables?
either cant read files for infile or there are ambiguous target names for outfile?

5

Your sample is not quite consistent - adding "out" once but "_out" the other time. If you just want the output files distinguished from the input files, try

$ awk '{gsub(",","."); print >FILENAME".out"}' *.dat

If you insist on "out" being introduced BEFORE the ".dat", try

$ awk '{gsub(",","."); fn=FILENAME; sub (".dat","out&",fn); print >fn}' *.dat
6 
$ awk '{gsub(",","."); print >FILENAME".out"}' *.dat

this awk works fine for me but now I would like to limit the number of column
to 41?
so how can I only output line 1 to 41 to the new outfile?

regards

rolli

7

try using cut command

along with the awk with a pipe

cut -c1-41

it may work.
i dnt knw for sure, even i am new to unix.

8

line or column? How about phrasing requests carefully?

9

the sed works:

sed '42,$d' infile > outfile

but how to do this for all files in folder ... same question again?

---------- Post updated at 06:32 AM ---------- Previous update was at 06:31 AM ----------

line is what I desire... I was mixed up... sorry

10 
$ awk ' FNR <= 41 {gsub(",","."); print >FILENAME".out"}' *.dat

(untested)

11 
sed '42,$d' infile > outfile

Just a suggestion. The above is OK, but it is better in several says to just say head -n 41 infile > outfile