Get the index of a specific string from a dynamically generated output - linux

Question

I tried a lot of things, but now I am at my wit's end.
My problem is I need the index of a specific string from my dynamically generated output.
In example, I want the index from the string 'cookie' in this output:
1337 cat dog table cookie 42
So in this example I would need this result:
5
One problem is that I need that number for a later executed awk command. Another problem is that this generated output has a flexible length and you are not able to 'sed' something with . - or something else. There is no such pattern like this.
Cheers

Answer 1

Just create an array mapping the string value to it's index and then print the entry:
$ cat file
1337 cat dog table cookie 42
$ awk -v v="cookie" '{v2i[v]=0; for (i=1;i<=NF;i++) v2i[$i]=i; print v2i[v]}' file
5
The above will print 0 if the string doesn't exist as a field on the given line.
By the way, you say you need that number output from the above "for a later executed awk command". Wild idea - why not do both steps in one awk command?

Answer 2

Ugly, but possible:
echo '1337 cat dog table cookie 42' \
| tr ' ' '\n' \
| grep -Fn cookie \
| cut -f1 -d:

Answer 3

Here is a way to find position of word in a string using gnu awk (due to RS), and store it to a variable.
pat="cookie"
pos=$(echo "1337 cat dog table cookie 42" | awk '{print NF+1;exit}' RS="$pat")
echo "$pos"
5
If you do not have gnu awk
pat="cookie"
pos=$(echo "1337 cat dog table cookie 42" | awk '{for (i=1;i<=NF;i++) if ($i~p) print i}' p="$pat")
echo "$pos"
5

Answer 4

Here is pure bash way of doing it with arrays, no sed or awk or GNUs required ;-)
# Load up array, you would use your own command in place of echo
array=($(echo 1337 cat dog table cookie 42))
# Show what we have
echo ${array[*]}
1337 cat dog table cookie 42
# Find which element contains our pattern
for ((i=0;i<${#array[#]};i++)); do [ ${array[$i]} == "cookie" ] && echo $(($i+1)); done
5
Of course, you could set a variable to use later instead of echoing $i+1. You may also want some error checking in case pattern isn't found, but you get the idea!

Answer 5

Here is another answer, not using arrays, or "sed" or "awk" or "tr", just based on the bash IFS separating the values for you:
#!/bin/bash
output="cat dog mouse cookie 42" # Or output=$(yourProgram)
f=0 # f will be your answer
i=0 # i counts the fields
for x in $output; do \
((i++)); [[ "$x" = "cookie" ]] && f=$i; \
done
echo $f
Result:
4
Or you can put it all on one line, if you remove the backslashes, like this:
#!/bin/bash
output="cat dog mouse cookie 42" # Or output=$(yourProgram)
f=0;i=0;for x in $output; do ((i++)); [[ "$x" = "cookie" ]] && f=$i; done
echo $f
Explanation:
The "[[a=b]] && c" part is just shorthand for
if [a=b]; then
c
fi
It relies on shortcut evaluation of logicals. Basically, we are asking shell to determine if the two statements "a equals b" AND the statement "c" are both true. If a is not equal to b, it already knows it doesn't need to evaluate c because they already can't both be true - so f doesn't get the value of i. If, on the other hand, a is equal to b, the shell must still evaluate statement "c" to see if it is also true - and when it does so, f will get the value of i.

Answer 6

Pat="cookie"
YourInput | sed -n "/${Pat}/ {s/.*/ & /;s/ ${Pat} .*/I/;s/[[:blank:]\{1,\}[^[:blank:]\{1,\}/I/g
s/I\{9\}/9/;s/I\{8\}/8/;s/I\{7\}/7/;s/IIIIII/6/;s/IIIII/5/;s/IIII/4/;s/III/3/;s/II/2/;s/I/1/
p;q;}
$ s/.*/0/p"
if there is more than 9 cols, a more complex sed could be made or pass through a wc -c instead