Shell Script - awk, begin, for and print

 
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Operating Systems Linux Fedora Shell Script - awk, begin, for and print
# 8  
Old 08-31-2013
You could use shell arithmetics, but this is quite limited on some shells. On others, yes, you can.
# 9  
Old 08-31-2013
I understood that pointsb will hold the values of awk's execution

Code:
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  
Old 08-31-2013
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  
Old 09-01-2013
Quote:
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

Code:
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!
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