Sstrhsrtj

I have a file similar to the following :

x 0

1 x

1 1

and I am essentially trying to see if both fields are equal to one another or not for every row. But the problem is that this file contains x which can either hold the value of 0 or 1 -- but I am not sure how to set this in awk

I tried working with the following code that did not work, it only works if x is set to either 0 or 1, not both.

y=$(seq 1 2)

awk -v x="$y" '{ if ($1==$2) print "good" }' file

Please advise or let me know if any clarification is necessary, thank you.

A scalar variable in awk can only hold a single variable. You'll have to do something like this:

if (

    ($1 == "x" && ($2 == 0 || $2 == 1)) ||

    ($2 == "x" && ($1 == 0 || $1 == 1)) ||

    $1 == $2

) print "good"

You can't set a variable to multiple values in any ordinary programming language that I know of, but you may most certainly loop over a set of values with a variable.

Construct a shell loop around the awk code that runs for each value of x:

for x in 0 1; do

    printf 'Running with x=%dn' "$x"

    awk -v x="$x" 

        '$1 == "x" { $1 = x }

         $2 == "x" { $2 = x }

         $1 == $2  { printf("match on line %d: %d == %dn", NR, $1, $2) }' file.in

done

The awk code tests the two columns for the character x and (if true) sets it to the current value of the awk variable x (which is set on the command line).

If the columns later are the same, some output is produced.

With the given data, this produces the output

Running with x=0

match on line 1: 0 == 0

match on line 3: 1 == 1

Running with x=1

match on line 2: 1 == 1

match on line 3: 1 == 1

Alternatively, move the loop into awk (which doesn't look as nice):

awk -v x="$x" 

        '{ for (x=0; x<=1; ++x) {

               printf("x is %dn", x);

               if ($1 == "x") { a = x } else { a = $1 }

               if ($2 == "x") { b = x } else { b = $2 }

               if (a == b) { printf("match on line %d: %d == %dn", NR, a, b) }

           }

          }' file.in

Output:

x is 0

match on line 1: 0 == 0

x is 1

x is 0

x is 1

match on line 2: 1 == 1

x is 0

match on line 3: 1 == 1

x is 1

match on line 3: 1 == 1