Text processing

Question 1

use a command to prints second, fifth and seventh character from each line of the file.

Answer 1

$ cut -c 2,5,7 name.txt

Question 2

command prints starting from first character to end.
command prints starting position to the fifth character.

Answer 2

$ cut -c 1- state.txt

$ cut -c -5 state.txt

Question 3

when space is used as a field separator or delimiter to print words of each line.

Answer 3

$ cut -d “ “ -f 1 state.txt

Question 4

use a command to print the 1th and 4th column (field) in a file.

Answer 4

$ awk ‘{print $1,$4}’ employee.txt

Question 5

in awk print the first item along with the row number separated with ” – “ from each line.

Answer 5

$ awk ‘{print NR “- “ $1 }’ geeksforgeeks.txt

Question 6

use a command for Printing lines with more than 10 characters.

Answer 6

$ awk ‘length($0) > 10’ geeksforgeeks.txt

Question 7

To print the squares of first numbers from 1 to n say 6 in awk.

Answer 7

$ awk ‘BEGIN { for(i=1;i<=6;i++) print “square of”, i, “is”,i*i; }’

Question 8

use a search command to do a Case insensitive search.

Answer 8

$grep -i “UNix” geekfile.txt

Question 9

use a command to search and to Displaying only the matched pattern (word) you want to search in a file.

Answer 9

$ grep -o “unix” geekfile.txt

Question 10

use a command to Show line number while displaying the output using grep.

Answer 10

$ grep -n “unix” geekfile.txt

Question 11

use a command to display the lines that are not matching with the specified search string pattern.

Answer 11

$ grep -n “unix” geekfile.txt

Question 12

use 2 commands to search for multiple strings (words) in a file.

Answer 12

$grep –e “Agarwal” –e “Aggarwal” –e “Agrawal” geekfile.txt

egrep -i milo|dandi|denne geekfile.txt

Question 13

use 2 methods to sort a file and to write the output to a new file.

Answer 13

$ sort inputfile.txt > filename.txt
$ sort -o filename.txt inputfile.txt

Question 14

use a command option to Sort In Reverse Order:

Answer 14

$ sort -r inputfile.txt

Question 15

use a command option to sort the file with numeric data present inside.

Answer 15

$ sort -n filename.txt

Question 16

sort a file with numeric data in reverse order.

Answer 16

$ sort -nr filename.txt
(combination of 2 options)

Question 17

Use a command option to sorting a table on the basis of any column number. Also if that column is numeric.

Answer 17

$ sort -k 2 employee.txt
$ sort -k 2n employee.txt

Question 18

use a command option to sort and remove duplicates .

Answer 18

$ sort -u filename.txt

Question 19

use a command option to sort by month

Answer 19

$ sort -M filename.txt

Question 20

use a command option prints the number of words present in a file.

Answer 20

wc -w filename.txt

Question 21

use a command to convert lower case characters to upper case.

Answer 21

tr [a-z] [A-Z] < filename.txt
tr [:lower:] [:upper:] < filename.txt
$ cat greekfile | tr [a-z] [A-Z]

Question 22

use a command to translate white-space characters to tabs.

Answer 22

tr [:space:] “\t” <filename.txt
tr “ “ “\t” <filename.txt

Question 23

use a command to translate braces into parenthesis and redirect it to another file.

Answer 23

$ tr “{}” “()” <greekfile>newfile.txt</greekfile>

Question 24

use a command to squeeze a sequence of repetitive characters.

Answer 24

$ echo “Welcome To GeeksforGeeks” | tr -s “ “
tr -s “ “ <filename.txt

Question 25

use a command to delete specified characters.

Answer 25

$ echo “Welcome To GeeksforGeeks” | tr -d …. tr -d W
$ tr -d W <filename.txt