1

I am working on a ksh script whose scenario is as follows:

I have a text file for students' reports which contains details of students like:

Student_1
Name: ABC
Class:X
Head Teacher:SITA
Status: Pass 

Student_1
Name: ABCE
Class:X
Head Teacher:SITA
Status: Pass 

Student_2
Name:ABCD
Class:XI
Head Teacher:RYAN
Status: Fail

Student_50:
Name:MIKE
Class:X
Head Teacher:RYAN
Status:Fail

What I need to do is to

  1. Find the number of students by counting the lines that start with Student_N;

  2. Count how many students passed and how many students failed using the Status: line.

  3. Find the name of students whose name starts with A.

I tried numerous things including:

sed -n '/Student_i<< Status/,/Status/p' students_details.txt >> report_card.txt
sed '/^Student_i<< Status/,/)/Status/$/!d/Status/s/^Student_i<< Status (///Status/s/);$//' students_details.txt >> report_card.txt
sed '/^Student_i<< Status/,/)Status$/!d;s/^Student_i<< Status (//;s/);$//' students_details.txt >> report_card.txt
sed '/^pass/,/);$/!d;s/^pass (//;s/);$//' students_details.txt>> report_card.txt

My desired output files are:

  • For point 1:

    Student_1 : 2
    Student_2 : 1
    Student_50: 1
    
  • For Point 2:

    Pass: 2
    Fail: 2
    
  • For Point 3:

    Count of Students whose name starts with "A" : 3
    
11
  • What is it you are looking for? You mention you want to learn. However on this site you are likely to receive pre-chewed answers that may not advance your learning that much. One tip; you seem to believe that "i" has some special meaning. In the samples posted "i" is nothing more than the letter "i". – Bram Oct 22 '15 at 7:43
  • Edited the question. Hope u will understand. At least give some pointers to resolve the issue, instead of ignoring it. – A.K. Singh Oct 22 '15 at 8:46
  • Since your data appears to consist of structured data records, I'd look at using awk or perl in 'paragraph mode' rather than sed. FWIW I don't see the relevance of the ksh tag here since you seem to be looking for a solution using external text-processing tools rather than the shell itself. – steeldriver Oct 22 '15 at 10:17
  • @steeldriver yes i am also working on different options like i had used grep -n -w filename.txt but still i am not fully satisfied. – A.K. Singh Oct 22 '15 at 10:21
  • OK so here's a freebie to get you started: awk 'BEGIN{RS=""} END{print NR}' – steeldriver Oct 22 '15 at 10:30
2

Personally, I would do the whole thing in Perl:

$ perl -00ne '/^(Student_\d+)/ && $count{$1}++; 
              /Name:\sA/ && $As++; 
              /Status:\s*Pass/ ? $pass++ : $fail++; 
             END{
                print "$_ : $count{$_}\n" for keys(%count); 
                print "Pass: $pass\nFail:$fail\n"; 
                print "Student names starting with A: $As\n"
            }' file 
Student_2 : 1
Student_1 : 1
Student_50 : 1
Pass: 2
Fail:2
Student names starting with A: 2

If you insist on separate commands per operation, you could use:

$ awk '/^Student_/{a[$0]++} END{for(s in a){print s,a[s]}}' file 
Student_1 1
Student_2 1
Student_50: 1
$ perl -ne '$pass++ if /:\s*Pass/; $fail++ if /:\s*Fail/;
     END{print "Pass: $pass\nFail: $fail\n"}' file 
Pass: 2
Fail: 2
$ echo "Student names starting with A: $(grep -c "^Name:\s*A" file )"
Student names starting with A: 2
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  • Nice answer using Perl. Since the original file had white-spaces in the second block, I'd add a \s* between /^ and (Student_\d+). – Moreaki Mar 4 '19 at 23:44
  • 1
    @Moreaki good point, thanks. I'm pretty sure that was just a copy/paste error though. Note how there are other places in the file that aren't uniform (some have Name: foo and others Name:foo). I am guessing the actual file is uniform and produced by some software tool. – terdon Mar 4 '19 at 23:55

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