Shell Programming and Scripting

Good Morning,


I was wondering if anybody could tell me how to achieve the following, preferably with a little commenting for understanding.


I have 2 files, each with multiple rows with multiple columns.

I need to find each row where the value in column 1 of file 1 matches column 1 in file 2. I then need to compare the 4th column from the rows and if the value in file 2 is greater than in file 1 then output to a third file the matching column 1 value, the 2nd column value,the 4th column value in file 1 and file 2 and the difference between them.

An example should make the above clearer.

File 1

123 john blah 2
456 tony blah 7
789 michelle blah 9
111 james blah 3


File 2

135 gary blah 6
456 tony blah 13
789 michelle blah 4
111 james blah 19


So the below should be output to file 3:

456 tony 7 13 6
111 james 3 19 16


Many thanks in advance for any answers

Try...

Code:

 
awk 'NR==FNR{arr[$1]=$2","$4}NR!=FNR{for(i in arr){split(arr[i],ss,",");
if(i==$1 && ss[2]<$4) print i,ss[1],ss[2],$4,$4-ss[2]}}' file1 file2

Worked 100% perfectly.

You're an absolute star mate

Not sure how the bits award thing works, but did it (hopefully correctly).

Code:

awk 'NR==FNR{arr[$1]=$2","$4}NR!=FNR{for(i in arr){split(arr[i],ss,",");
if(i==$1 && ss[2]<$4) print i,ss[1],ss[2],$4,$4-ss[2]}}' file1 file2

I was trying to understand how this command works...

I get this error when I try to run this command. Please help debug this..

awk: arr is not an array
record number 1

it is not giving me that kind of error when i run that code, may be you better try with nawk or gawk inplace of awk.

Wow! nawk works for me.

This example works, I have a little more complicated comparison opperation. I have an index of IDs. These IDs are part of several substrings of a file. I want to see which IDs are in the file and which ones are not. Here are a few lines.

23873_ChemDiv_000A-0001
AVtclcactv01291016372D 0 0.00000 0.00000 1

31 34 0 0 0 0 0 0 0 0999 V2000

The ID is the first 5 characters of this string 23873_ChemDiv_000A-0001