Visit The New, Modern Unix Linux Community

Shell Script - awk, begin, for and print

Thread Tools Search this Thread
Operating Systems Linux Fedora Shell Script - awk, begin, for and print
# 8  
You could use shell arithmetics, but this is quite limited on some shells. On others, yes, you can.
# 9  
I understood that pointsb will hold the values of awk's execution

pointsb = 'final result of awk'

What does that awk do?

It does some looping and prints x,y values. I assume it will be stored in pointsb.
so pointsb might be holding something like this.

pointsb = 1,2 4,5 2,3 5,6
is that right?

Or what does awk return to pointsb?
I am not able to guess this. How does the variable assign work here?
# 10  
Read your shell's man page on command substitution.
Read the awk man page. It's a very powerful pattern scanning and text processing language.
# 11  
Originally Posted by RudiC
Read your shell's man page on command substitution.
Read the awk man page. It's a very powerful pattern scanning and text processing language.
Your replies saved lot of time in learning shell script and made life easier Smilie

* I downloaded Fedora 19
* I installed it in my laptop
* I created that simple shell script and executed to know the pointsb value with some dummy values of other variables
* I created another shell script without awk

pointsb = ""
for (y=yc; y<=yb; y++) { 
    x = a2*y*y+b2*y+c2; 
    pointsb = "$pointsb $x $y "

The logic is completely right in the above code apart from the system mistakes. I am sure i am not going to write any shell script. I just wanted to learn it. So when i read a script, i could understand the flow.

Have a good day!

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #431
Difficulty: Medium
JavaScript arrow functions were first introduced in 6th Edition - ECMAScript 2015.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Need awk or Shell script to compare Column-1 of two different CSV files and print if column-1 matche

Example: I have files in below format file 1: zxc,133, cst,222, File 2 Contains: hxd hcd jws zxc cst File 1 has 50000 lines and file 2 has around 30000 lines : Expected Output has to be : hxd hcd jws (5 Replies)
Discussion started by: TestPractice
5 Replies

2. Shell Programming and Scripting

Usage of a variable in awk BEGIN

Hi, diffcount=`awk 'BEGIN { while ( getline < "/scripts/matt/text.server1.reference" ) { arr++ } } { if (!( $0 in arr ) ) { print } }' $TMPDIR/$(basename $0 .sh) | wc -l` if ]; then OK="OK - No change in the interfaces status" elif ]; then DIFF=`awk 'BEGIN {... (4 Replies)
Discussion started by: nms
4 Replies

3. Shell Programming and Scripting

Awk: BEGIN: prints nothing

My code fails to do anything if I've BEGIN block in it: Run the awk script as: awk -f ~/bin/sum_dupli_gene.awk make_gene_probe.txt #!/usr/bin/awk -f BEGIN { print ARGV #--loads of stuff } END{ #more stuff } (14 Replies)
Discussion started by: genome
14 Replies

4. UNIX for Dummies Questions & Answers

awk search with begin

Hi, I have written below script to begin if the line has n #!/bin/ksh /usr/xpg4/bin/awk {/ n / 'BEGIN {X = "01"; X = "02"; X = "03"; X = "04"; X = "05"; X = "06"; X = "07"; X = "08"; X ="09"; X = "10"; X = "11"; X = "12"; };} NR > 1 {print $1 "\t" $5 "," X "," $6 " " $7}'} input.txt |... (9 Replies)
Discussion started by: stew
9 Replies

5. Shell Programming and Scripting

How to print backslash in shell script using awk?

I found that echo "aaa" | awk '{print ",\\";}' works, and it will give "\". but ddd=`echo "aaa" | awk '{print ",\\";}'`; echo $ddd will not work. Could anyone tell me why? thank you. (8 Replies)
Discussion started by: wxuyec
8 Replies

6. Shell Programming and Scripting

strange: sed and awk print at end instead of begin of line

Hi! I have a strange behaviour from sed and awk, but I'm not sure, if I'm doing something wrong: I have a list of words, where I want to add the following string at the end of each line: \;\;\;\;0\;1 I try like this: $ cat myfile | awk '{if ( $0 != "" ) print $0"\;\;\;\;0\;1"}' Result:... (5 Replies)
Discussion started by: regisl67
5 Replies

7. Shell Programming and Scripting

awk/shell script to print each line to a file

Dear People, My query is: have a file, which looks likes this: 10 20 30 40 50 1 2 3 4 5 100 200 300 400 500 what i need is: "PRINT EACH LINE TO AN UNIQUE FILE" desired output: file 1 10 20 30 40 50 file 2 1 2 3 4 5 (3 Replies)
Discussion started by: saint2006
3 Replies

8. Shell Programming and Scripting

shell script(Preferably awk or sed) to print selected number of columns from each row

Hi Experts, The question may look very silly by seeing the title, but please have a look at it clearly. I have a text file where the first 5 columns in each row were supposed to be attributes of a sample(like sample name, number, status etc) and the next 25 columns are parameters on which... (3 Replies)
Discussion started by: ks_reddy
3 Replies

9. Shell Programming and Scripting

awk BEGIN problem

awk 'BEGIN { print "line one\nline two\nline three" }' After ./ Usage: awk -f progfile file ... Usage: awk 'program' file ... POSIX options: GNU long options: -f progfile --file=progfile -F fs --field-separator=fs -v var=val ... (7 Replies)
Discussion started by: cola
7 Replies

10. Shell Programming and Scripting

awk getting stuck after BEGIN

I am beginner in awk awk 'BEGIN{for(i=1;(getline<"opnoise")>0;i++) arr=$1}{print arr}' In the above script, opnoise is a file, I am reading it into an array and then printing the value corresponding to index 20. Well this is not my real objective, but I have posted this example to describe... (1 Reply)
Discussion started by: akshaykr2
1 Replies

Featured Tech Videos