while loop in awk function

skuz_ball · 03-10-2010, 12:47 AM

I am having an issue getting the correct syntax right when I use a while loop inside an awk function. I am using ksh to basically multiply series of numbers that I have generated from a while loop with another number.

The following part of the script is where I encounter problems:

var=4

i=1
while ((i <= $var))

do

answer[i]=$(awk BEGIN'{print '$number[i]'*0.0174533}')
let i=i+1

done

The $number[i] variable has already been identified beforehand and works fine.

The error I am getting is as follows:

syntax error The source line is 1.
The error context is
BEGIN{print >>> [ <<<
awk: The statement cannot be correctly parsed.

The square brackets [ ] seem to be the issue but I have tried using a few different alternatives but nothing seems to work. Can anyone please suggest a way of making the above awk statement work? It would be much appreciated.

grail · 03-10-2010, 01:25 AM

Hi skuz_ball

Assuming you are getting $number[i] from elsewhere in the script I think you need to
set the variable out side:

ie. awk -v num=${number[i]} BEGIN'{ print num * 0.0174533 }'

catkin · 03-10-2010, 02:59 AM

Quote:

Originally Posted by grail

Hi skuz_ball

Assuming you are getting $number[i] from elsewhere in the script I think you need to
set the variable out side:

ie. awk -v num=${number[i]} BEGIN'{ print num * 0.0174533 }'

That would work. Alternatively it could be substituted by its value at the same time as the shell expands the expression inside $() by using the necessary {} in the array reference:

Code:

$(awk BEGIN '{print '${number[i]}'*0.0174533}')