Shell Programming and Scripting

Hello!
Please could anyone help me in writing a code to modify the value in column
two of a file with more than two tab-separated column (but the lines
may have a different number of columns, i.e. more or less columns),
according to the following conditions.

When the value of column two is "V", look in the whole field (string)
present in column three of that line to find if is there any of this
strings: IMP or VFIN or INF or SBJN or COND:ki. If one of these ir
found there, its value should be put in column two (instead of "V",
which was there).

Moreover, if in column three the string REL is present also, it should
be printed too, like this ":rel"at the end of the new value of column
two.

Look to the sample here below:

Code:

tolewa V 7/8-SG-SP VFIN PAST 7/8-SG-REL SVO EXT: APPL PASS :EXT"
trans="put out , remove" kilichotolewa
mwaka N 3/4-PL miaka
, COMMA ,
jenga V INF SVO kuijenga
anguka V 9/10-SG-SP COND:ki" trans=break down" ikianguka
 
to obtain:

tolewa VFIN:rel 7/8-SG-SP VFIN PAST 7/8-SG-REL SVO EXT: APPL PASS
:EXT" trans="put out , remove" kilichotolewa
mwaka N 3/4-PL miaka
, COMMA ,
jenga INF INF SVO kuijenga
anguka COND:ki 9/10-SG-SP COND:ki" trans=break down" ikianguka

Thank you very much!
mjomba

You need gawk:

Code:

awk '/ V / {$0=gensub(/(.+) (V) (.*)(VFIN|INF|COND:ki|IMP|SBJN)(.+)/, "\\1 \\4 \\3 \\4\\5", "g")} 
             {if ($0~/REL/) $2=$2 ":rel" }1' infile

Dear rdcwayx,
thank you for the code you wrote!

I slightly changed it as follows, and tried it on CygWin, but I got a message of error which I don't understand. Could you help me?
Thank you again!
Mjomba

Code:

Name@user ~/data
$ ./xml2tab.sh
./xml2tab.sh: line 44: syntax error near unexpected token `('
./xml2tab.sh: line 44: `      awk '/\tV\t/ {$0=gensub(/(.+)\t(V)\t(.*)(VFIN|SBJN
|INF |COND:ki|IMP|PRO)(.+)/, "\\1 \\4 \\3 \\4\\5", "g")}{if ($0~/REL/) $2=$2 ":r
el" }1' HCS_all.tab > HCS_all.tab.pul'

Name@user/data

Code:

`      awk '/\tV\t/ {$0=gensub(/(.+)\t(V)\t(.*)(VFIN|SBJN
|INF |COND:ki|IMP|PRO)(.+)/, "\\1 \\4 \\3 \\4\\5", "g")}{if ($0~/REL/) $2=$2 ":r
el" }1' HCS_all.tab > HCS_all.tab.pul'

Seems the command ` is not in pair of.

Dear rdcwayx.
Could you explain, please, the meaning of the number which follow \\ after gensub ?
Thank you very much. Mjomba

Here is the explain on how to use gensub function in gawk.

String Functions - The GNU Awk User's Guide

gensub(regexp, replacement, how [, target]) #

gensub is a general substitution function. Like sub and gsub, it searches the target string target for matches of the regular expression regexp. Unlike sub and gsub, the modified string is returned as the result of the function and the original target string is not changed. If how is a string beginning with ‘g’ or ‘G’, then it replaces all matches of regexp with replacement. Otherwise, how is treated as a number that indicates which match of regexp to replace. If no target is supplied, $0 is used.
gensub provides an additional feature that is not available in sub or gsub: the ability to specify components of a regexp in the replacement text. This is done by using parentheses in the regexp to mark the components and then specifying ‘\N’ in the replacement text, where N is a digit from 1 to 9. For example:

$ gawk '
> BEGIN {
> a = "abc def"
> b = gensub(/(.+) (.+)/, "\\2 \\1", "g", a)
> print b
> }'
-| def abc
As with sub, you must type two backslashes in order to get one into the string. In the replacement text, the sequence ‘\0’ represents the entire matched text, as does the character ‘&’.

The following example shows how you can use the third argument to control which match of the regexp should be changed:

$ echo a b c a b c |
> gawk '{ print gensub(/a/, "AA", 2) }'
-| a b c AA b c
In this case, $0 is used as the default target string. gensub returns the new string as its result, which is passed directly to print for printing.

If the how argument is a string that does not begin with ‘g’ or ‘G’, or if it is a number that is less than or equal to zero, only one substitution is performed. If how is zero, gawk issues a warning message.

If regexp does not match target, gensub's return value is the original unchanged value of target.

gensub is a gawk extension; it is not available in compatibility mode (see Options).