Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: help with columns and rows - script
Operating Systems Linux help with columns and rows - script Post 302531349 by Corona688 on Thursday 16th of June 2011 12:37:14 PM
Old 06-16-2011
Quote:
Originally Posted by yazu
POSIX shell
Code:
c=1
for f in `cat tmp.file`; do
  if [ $(($c % 15)) -ne 0 ]; then
    printf "$f "
  else
    echo
  fi
  c=$((c + 1))
done

  1. This is a combo useless use of cat and useless use of backticks. Loading an entire file into a variable to chop it like this is especially dangerous since, if the file is larger than the maximum size of a shell variable, the end will get chopped off.
  2. You shouldn't feed variables into printf's command string unless you can control exactly what they are. It will throw up on or mangle anything with % or \ in it.
  3. It ignores every fifteenth cell.
  4. It may end up printing the last line without an ending line-feed, which may prevent the last line from being read by various UNIX utilities like sed and awk.
  5. It would require a KSH or KSH-like shell, for the $(( )) math syntax.

Code:
c=0
MAX=15
PREFIX=""
# read lines
while read f
do
        # split lines into $1, $2, ...
        set -- $f
        for d in $*
        do
                if [ `expr $c % $MAX` -eq 0 ]
                then
                        # PREFIX being blank prevents extra blank line on the very first line
                        printf "${PREFIX}%s" "$d"
                        PREFIX="\n"
                else
                        printf " %s" "$d"
                fi

                c=`expr $c + 1`       
        done
done < tmp.file

echo

Last edited by Corona688; 06-16-2011 at 01:50 PM..
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

shell script required to convert rows to columns

Hi Friends, I have a log file as below siteid = HYD spc = 100 rset = RS_D_M siteid = DEL spc = 200 rset = RS_K_L siteid = DEL2 spc = 210 rset = RS_D_M Now I need a output like column wise as below. siteid SPC rset HYD 100 RS_D_M (2 Replies)
Discussion started by: suresh3566
2 Replies

2. Shell Programming and Scripting

perl script to print to values in rows and columns

Hi guys I want to print the values by using this script but its giving the no of rows and columns as input instead of values Would you plz help me on this FILE- chr1.txt 1981 1 1971 1 1961 1 1941 1 perl script #!/usr/bin/perl -w $infile1 = 'chr1.txt'; $outfile3 = 'out3.txt'; ... (3 Replies)
Discussion started by: nogu0001
3 Replies

3. Shell Programming and Scripting

sql output from multiple rows and columns as variables in a script

This is for an Oracle journal import. I was using a pl/sql package and oracle API's. Oracle added invoker rights to their API's and now my package won't run. I didn't want to use their API's anyway. The only reason i was using pl/sql and the API's (just a package) was to utilize a cursor. How... (2 Replies)
Discussion started by: lmu
2 Replies

4. Shell Programming and Scripting

Script - columns to rows

Hi Everyone, I have a file text.cvs, which is a file with columns from excel. The data are separeted with semicolon. The content of the file looks like A B C D E F 1 3 3 4 3 3 2 2 1 2 5 2 5 6 1 1 2 1 Now I wish to write an script which writes the colums A, C and F in... (4 Replies)
Discussion started by: Tob26
4 Replies

5. Shell Programming and Scripting

Converting rows to columns using shell script

I have a script which converts rows to columns. file_name=$1 mailid=$2 #CREATE BACKUP OF ORIGINAL FILE #cp ${file_name}.xlsx ${file_name}_temp.xlsx #tr '\t' '|' < ${file_name}_temp.xlsx > ${file_name}_temp.csv #rm ${file_name}_temp.xlsx pivot_row=`head -1 ${file_name}` sed 1d... (3 Replies)
Discussion started by: andy538
3 Replies

6. Shell Programming and Scripting

Convert columns to rows in perl script

Hi All I want to have a Perl script which convert columns to rows. The Perl should should read the data from input file. Suppose the input file is 7215484 date to date 173.3 A 1.50 2.23 8.45 10.14 2.00 4.50 2.50 31.32 7216154 month to month (3 Replies)
Discussion started by: parthmittal2007
3 Replies

7. UNIX for Dummies Questions & Answers

Writing a script to take the average of two columns every 3 rows

I have a dataset with 120 columns. I would like to write a script, that takes the average of every two columns, starting from columns 2 and 3, and moving consecutively in frames of 3 columns, all the way until the last column. The first column in the output file would be the averages of columns... (1 Reply)
Discussion started by: evelibertine
1 Replies

8. Shell Programming and Scripting

Shell script to convert rows to columns

Hi I have a file having the values like below ---------------------------- .set A col1=”ABC” col2=34 col3=”DEF” col4=”LMN” col5=25 .set A .set B col1=55 col3=”XYZ” col4=”PQR” col5=66 .set B .set C col2=”NNN” (1 Reply)
Discussion started by: Suneel Mekala
1 Replies

9. Shell Programming and Scripting

Help with shell script: selecting rows that have the same values in two columns

Hello, everyone I am beginner for shell programming. I want to print all lines that have the same values in first two columns data: a b 1 2 a a 3 4 b b 5 6 a b 4 6 what I expected is : a a 3 4 b b 5 6 but I searched for one hour in... (2 Replies)
Discussion started by: nengcheng
2 Replies

10. Shell Programming and Scripting

Help with script to convert rows to columns

Hello I have a large database with the following structure: Headword=Gloss1;Gloss2;Gloss3 The Glosses are separated by a ; What I need is to reduce the multiple glosses on each row to columns Headword=Gloss1 Headword=Gloss2 Headword=Gloss3 I had written the following script in awk... (5 Replies)
Discussion started by: gimley
5 Replies

LEARN ABOUT HPUX

read

read(1) 						      General Commands Manual							   read(1)

NAME

       read - read a line from standard input

SYNOPSIS

       var ...

DESCRIPTION

       reads  a single line from standard input.  The line is split into fields as when processed by the shell (refer to shells in the first field
       is assigned to the first variable var, the second field to the second variable var, and so forth.  If there are more fields than there  are
       specified  var  operands,  the remaining fields and their intervening separators are assigned to the last var.  If there are more vars than
       fields, the remaining vars are set to empty strings.

       The setting of variables specified by the var operands affect the current shell execution environment.

       Standard input to can be redirected from a text file.

       Since affects the current shell execution environment, it is usually provided as a normal shell special (built-in) command.  Thus, if it is
       called  in  a  subshell	or  separate utility execution environment similar to the following, it does not affect the shell variables in the
       caller's environment:

   Options
       recognizes the following options:

	      Do not treat a backslash character in any special way.
		     Consider each backslash to be part of the input line.

   Opperands
       recognizes the following operands:

	      var    The name of an existing or nonexisting shell variable.

EXTERNAL INFLUENCES

   Environment Variables
       determines the internal field separators used to delimit fields.

RETURN VALUE

       exits with one of the following values:

	       0     Successful completion.

	      >0     End-of-file was detected or an error occurred.

EXAMPLES

       Print a file with the first field of each line moved to the end of the line.

	      while read -r xx yy
	      do
		      printf "%s %s 
" "$yy" "$xx"
	      done < input_file

SEE ALSO

       csh(1), ksh(1), sh(1), sh-posix(1).

STANDARDS CONFORMANCE

																	   read(1)
All times are GMT -4. The time now is 03:15 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy