Regular Expression help 1

[learningawk]

I am having trouble understanding how regular expressions work using AWK.
I am trying to match certain characters in a substr field.
For example:
field 1=123-2N
if (match ($1,/^[1][0-9][0-9].?[N])) { print}

In my input file I have several different combinations of like data, such as:

field 1=123-2N
field 1=123-2N1
field 1=123-2N11
field 1=123-2Nb
field 1=223-2N
I would only like the match to occur when it finds a match on the input of
123-2N

Thanks for helping.
I need a quick problem to be solved.

 

[vgersh99]

BEGIN {
FS=OFS="="
}

$2 ~ /^1[0-9][0-9]*-[0-9]N/
vlad
+----------------------------+
| #include<disclaimer.h> |
+----------------------------+

 

[marsd]

It looks like you are confused about how awk
works to me.

Any of these approaches will work:

fld1="123-2N" ; if ($1 ~ fld1) {print}
if ($1 ~ /[0-9]+-[0-9][A-Z]/)  {print $1}
if ( (match($1,//[0-9]+-[0-9][A-Z]/)) {
    print substr($1,RSTART,RLENGTH)
}

But they all do different things.

 

[learningawk]

Thanks for the response.

Can you also hint on how I would search for the field=
123-2N11 and not the others or all of the records that would contain an start with 1 and have a &quot;N&quot; somewhere following.

Thanks

 

[marsd]

Try this:
for (i=1 ; i <= NF ; i++) {
if ($i == &quot;123-2N11&quot; || $i ~ /1.*N/) {
print $i
}
}

 

[learningawk]

Thanks,
I really need a one liner to do the match statement, since I have a script that would include several hundred of these similar match and print statements.

Just to clariy:
I have a file that has similar but unique character strings such as:
123-2N
123-2N1
123-2N11
123-2Nb
223-2N

on different records, and I would like to specifically set some action statements based on the pattern match and then some global actions for like fields.

Depending on the circumstance, I could set the action based on /^1[0-9][0-9] with a N anywhere in the string or I may want to match on specifically /^1[0-9][0-9]b$

Thanks for helping me understand how regular expressions work.

 

[marsd]

I'm having trouble following what you want to do and why
you want to use match() so badly and why you have to have
&quot;one-liners&quot;, etc...
This does what you first described.
if ($0 ~ /^1[0-9]+-.*N/) {print}

If you have some conditional searches you need to do
after a certain line is read I think you are doing things
the hard way, but you could functionally wrap match() if thats what you are getting at.

function searchPat(line,pat) {
    if ( (match(line,pat)) ) {
         return substr(line,RSTART,RLENGTH)
    }
return "NULL"
}

 

[learningawk]

Yea,

The statment :

if ($0 ~ /^1[0-9]+-.*N/) {print}

is performing what I need it to do.

Thanks