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Full Discussion: Awk: problem for loop through variable
Top Forums UNIX for Dummies Questions & Answers Awk: problem for loop through variable Post 302948864 by Akshay Hegde on Friday 3rd of July 2015 08:04:40 AM
Old 07-03-2015
Quote:
Originally Posted by beca123456
Hi CarloM,

I tried:
Code:
gawk 'BEGIN{FS=OFS="|"}

function repeat(str, n, rep, i){
    for(i=1; i<=n; i++)
        rep=rep str
        return rep
}
{

# when awk reads first record 
# $2 = 1, j is undefined or not set yet and -1
# which is nothing but $2+(j-1) = 0
# so loop inside function repeat will not work
# ultimately function returns rep which is undefined or not set yet
# so a[""] = ""
# since variable_j is not defined or not set
a[variable_j]=repeat($1, $2+(j-1))  

for(k in a){
    # iterate 3 times since contents inside array a is just ""  you received blank output
    for(j=1; j<=3; j++){
        print a[k]
}
}
}' input

but still get blank records...
Here is test

Code:
[akshay@localhost tmp]$ echo "AAA|1" | gawk 'BEGIN{FS=OFS="|"}
function repeat(str, n, rep, i){ 
print "n : "n
    for(i=1; i<=n; i++)
        rep=rep str
        return rep
}
{

a[variable_j]=repeat($1, $2+(j-1))  

for(k in a){
    for(j=1; j<=3; j++){
        print k,a[k]
}
}

}' 
n : 0
|
|
|

This User Gave Thanks to Akshay Hegde For This Post:
beca123456
 

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LEARN ABOUT MOJAVE

repeat

textutil::repeat(n)				    Text and string utilities, macro processing 			       textutil::repeat(n)

__________________________________________________________________________________________________________________________________________________

NAME

       textutil::repeat - Procedures to repeat strings.

SYNOPSIS

       package require Tcl  8.2

       package require textutil::repeat  ?0.7?

       ::textutil::repeat::strRepeat text num

       ::textutil::repeat::blank num

_________________________________________________________________

DESCRIPTION

       The package textutil::repeat provides commands to generate long strings by repeating a shorter string many times.

       The complete set of procedures is described below.

       ::textutil::repeat::strRepeat text num
	      This  command returns a string containing the text repeated num times. The repetitions are joined without characters between them. A
	      value of num <= 0 causes the command to return an empty string.

	      Note: If the Tcl core the package is loaded in provides the command string repeat then this  command  will  be  implemented  in  its
	      terms, for maximum possible speed. Otherwise a fast implementation in Tcl will be used.

       ::textutil::repeat::blank num
	      A convenience command. Returns a string of num spaces.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain bugs and other problems.  Please report such in the category textutil
       of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883].  Please also report any ideas for enhancements you may have for
       either package and/or documentation.

SEE ALSO

       regexp(n), split(n), string(n)

KEYWORDS

       blanks, repetition, string

CATEGORY

       Text processing

textutil							       0.7.1						       textutil::repeat(n)
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