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For loop using 2 files

 
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# 8  
Old 02-02-2009
You are correct in the code above...

and because of the second false condition, we would print nothing and move onto the second line in file2, where 38>=30 (true) AND 41<=44 (true) hence here we would print 30,44(file1) and then int this way we would continue to loop file2 until the end
# 9  
Old 02-02-2009
Do you get the desired result with the following code?

Use GNU awk (gawk), New awk (nawk) or POSIX awk (/usr/xpg4/bin/awk):

Code:
awk '(getline f2 < F2) > 0 {
  split(f2, t)
  if (t[1] >= $1 && t[2] <= $2)
    print 
    }' F2=file2 file1

# 10  
Old 02-02-2009
Basically, we would would be doing this conditional check for each line in file2 against each line in file1. I have something like this:

Code:
awk -F, '\
BEGIN {
while ((getline < "file2") > 0)
file2[$2]=$3
}
{for (col1 in file2)
if ($0>=30 && $1<=44)
print $0} ' FILE1

but here is where I am stuck: I have hard-coded the number 30 and 44..this should refer to column1 and column 2, from file1 and print from FILE1 if the conditional statement is true.

Cheers for any solutions
Last edited by radoulov; 02-02-2009 at 07:48 AM.. Reason: added code tags
# 11  
Old 02-02-2009
Try the solution above and let me know.
# 12  
Old 02-02-2009
Maybe something like this (not tested):

Code:
awk 'NR==FNR{a[++i]=$1;b[i]=$2;next}
{ for(j=1;j<=i;j++){
   if(a[j] >= $1 && b[j] <= $2{print;break}
  }
}' file2 file1

Regards
# 13  
Old 02-02-2009
Thankyou to both of you. Both work well..but I would like to take a minute to understand the code

Code:
awk '(getline f2 < F2) > 0 {
  split(f2, t) # you split the columns in File 2?  t means tab delimiter?
  if (t[1] >= $1 && t[2] <= $2) # How does the code know that $2 and $1 come from file1
    print 
    }' F2=file2 file1

Last edited by radoulov; 02-02-2009 at 08:31 AM.. Reason: added code tags
# 14  
Old 02-02-2009
Quote:
you split the columns in File 2? t means tab delimiter?
From the GNU awk manual:

Quote:
split(string, array [, fieldsep])
This function divides string into pieces separated by fieldsep and stores the
pieces in array. The first piece is stored in array[1], the second piece in
array[2], and so forth. The string value of the third argument, fieldsep, is a
regexp describing where to split string (much as FS can be a regexp describing
where to split input records). If fieldsep is omitted, the value of FS is used.
t is the array name, fieldsep defaults to the current value of FS.

Quote:
How does the code know that $2 and $1 come from file1
Because awk reads the files in parallel,
in the block above both $0 (the current record from file1 and f2 (the current record from file2 via getline) are available.

Hope this helps.
 
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