Passing more than one variable from the shell to AWK? 1

[fusi0n]

Hi!

I'm having some problems getting AWK to use more than one variable from the shell. In a long bit of code I have the snippet:

suf=00"$i"
molwsuf="$molname"_"$suf"_hbond
h=`cat $molwsuf`
gawk '/'"$molname"_"$suf"'/ {print '"$i"', $2, $4, $6, '"$h"'}' $logfile >> $filename

Where i is an integer that increases by one for every while [ $i -le 9 ] loop. h is either 'no' or 'bond', as defined by a previous condition which then outputs no or bond to the file $molwsuf.

Everything works fine, except for the '"$h"' part. The output I get is:

0 7.51 -2.71 1.93
1 6.79 -1.95 2.26
2 6.70 -1.74 2.17
3 6.63 -2.44 2.31
4 6.56 -2.82 2.63
5 6.44 -3.10 2.68
6 6.23 -2.84 2.60
7 6.09 -2.90 2.66
8 5.95 -3.76 2.27
9 5.68 -4.15 2.78

Which is missing the $h variable (another column at the end). When I echo the gawk line, I get:

gawk '/'c5_nod_r_ou_oz_ar_009'/ {print '9', , , , 'no'}' R500log >> c5_nod_r_ou_oz_ar_tab.log

So the variable is being passed correctly, it's just not being printed (?).

Is there a limit to variables being passed to a single awk strand?

I have tried this using 'X' and 'o' instead of 'no' and 'bond', moving the '"$h"' to various places in the string, and using '"$hb"' instead.

What's going on? Why can't I use more than the one variable? Any ideas on how to get this to correctly print the string?

Thanks so much!

 

[feherke]

Hi

Passing more than one variable from the shell to AWK?

Passing variable from shell to [tt]awk[/tt] means this :

awk -v var1=val1 -v var2=val2 'BEGIN{ print "I got " var1 " and " var2 }'

Feherke.

http://rootshell.be/~feherke/

 

[fusi0n]

My apologies for the incorrect thread title. I'm still very new to this and thought I was having problems passing more than one 'shell' variable into my awk string.

What would a more appropriate summary of the problem be? Any ideas on how to fix it?

Thanks!

 

[feherke]

Hi

[gray]# the shell transforms this :[/gray]
gawk '/'"$molname"_"$suf"'/ {print '"$i"', $2, $4, $6, '"$h"'}' $logfile >> $filename

[gray]# into this :[/gray]
gawk '/'???_???'/ {print 0, $2, $4, $6, [red]no[/red]}' $logfile >> $filename
        [red]this looks like a variable name ^^[/red]

[gray]# so provide double quotes ( " ) for it :[/gray]
gawk '/'"$molname"_"$suf"'/ {print '"$i"', $2, $4, $6, [red]"[/red]'"$h"'[red]"[/red]}' $logfile >> $filename

Feherke.

http://rootshell.be/~feherke/

 

[fusi0n]

Fantastic! That worked like a charm.

Thank you very much for the fix! And thank you for explaining what the problem was.

 

[PHV]

And what about this ?
gawk "/${molname}_$suf/ {print $i, \$2, \$4, \$6, \"$h\"}" $logfile >> $filename

Hope This Helps, PH.
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