How to change certain field separated by comma

[rashidaq]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

if done in PERL easily then I have to learn that too.

thanks in advance
Rashid

 

[Enrique Perez-Terron]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

if done in PERL easily then I have to learn that too.

thanks in advance
Rashid

awk -F, 'BEGIN {OFS=","}
/FirstsPattern/,/LastPattern/{$6="TheReplacement"; print}'

-Enrique

 

[Ed Morton]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

awk -F, 'NR>1&&NR<1877{$6=newText}1'

Regards,

Ed.

 

[Jürgen Exner]

I have file which is separated by commas.
This is like csv file, [...]

Then why not just use the Text::CSV module?

jue

 

[Kenny McCormack]

I have file which is separated by commas.
This is like csv file, [...]

Then why not just use the Text::CSV module?

Ah, the dangers of cross-posting.

It should be a rule (i.e., convention) that when respoding to
a cross-posted item, you must identiy which group you are posting from.

(Posting from comp.unix.shell, hence having no idea what a "Text::CSV"
is... [*])

[*] Not true, of course. I recognize that as a Perl thing, so I am
assuming that you are posting from one of the Perl groups, and didn't check
the "Newsgroups" line before posting.

 

[Joe Smith]

awk -F, 'BEGIN {OFS=","}
/FirstsPattern/,/LastPattern/{$6="TheReplacement"; print}'

And now for a perl solution:

linux% cat Temp
BEGIN {FS=OFS=","} /FirstsPattern/,/LastPattern/{$6="TheReplacement";
print}
linux% a2p Temp
#!/usr/bin/perl
eval 'exec /usr/bin/perl -S $0 ${1+"$@"}'
if $running_under_some_shell;
# this emulates #! processing on NIH machines.
# (remove #! line above if indigestible)

eval '$'.$1.'$2;' while $ARGV[0] =~ /^([A-Za-z_0-9]+=)(.*)/ && shift;
# process any FOO=bar switches

$[ = 1; # set array base to 1
$FS = ' '; # set field separator
$, = ' '; # set output field separator
$\ = "\n"; # set output record separator

$FS = $, = ',';

while (<>) {
chomp; # strip record separator
@Fld = split($FS, $_, 9999);
if (/FirstsPattern/ .. /LastPattern/) {
$Fld[6] = 'TheReplacement';
print join($,,@Fld);
}
}
linux%
-Joe

 

[Damian James]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

Is it really CSV, or as you say just database fields separated by
commas? There are no commas in the fields? If there are, how are
they escaped? Does this format use quote characters?

Actual CSV is annoying to parse, and if you were writing a script to
manipulate these files in Perl, you'd probably want to use the
Text::CSV module as advised elswhere in this thread.

...
:2,1876s/$/stringtobeAppended/g and it works but
now how do I replace in the middle like field number 6 separated by
commas on certain line range.

You've had a couple of awk answers, which probably make the most
sense for a one liner.

if done in PERL easily then I have to learn that too.

Perl one liner for completeness:

perl -F, -lane '$F[6] = "new" if 2..1876; print join ",", @F' filename

I'm sure others in clpm can golf that down somewhat

--Damian

 

[William James]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

if done in PERL easily then I have to learn that too.

thanks in advance
Rashid

awk 'BEGIN{FS=OFS=","}NR>1,NR<1877{$6="new"}1' file

 

[Darren Dunham]

And now for a slightly more concise Perl solution:

#! /usr/bin/perl -w
while (<>)
{
my @fields = split (/,/);
$fields[6-1] = 'TheReplacement'
if 6 .. 1876;
print join (",", @fields);
}

The code is probably a little clearer if "if 6 .. 1876" is replaced
with its equivalent, "if $. == 6 .. $. == 1876". But then I was
going for brevity.

Or even...

perl -F, -ane '$F[5] =~ s/bob/sue/ if 6 .. 1876 ;print join(",",@F);'

 

[William James]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

Is it really CSV, or as you say just database fields separated by
commas? There are no commas in the fields? If there are, how are
they escaped? Does this format use quote characters?

Actual CSV is annoying to parse, and if you were writing a script to
manipulate these files in Perl, you'd probably want to use the
Text::CSV module as advised elswhere in this thread.

...
:2,1876s/$/stringtobeAppended/g and it works but
now how do I replace in the middle like field number 6 separated by
commas on certain line range.

You've had a couple of awk answers, which probably make the most
sense for a one liner.

if done in PERL easily then I have to learn that too.

Perl one liner for completeness:

perl -F, -lane '$F[6] = "new" if 2..1876; print join ",", @F' filename

I'm sure others in clpm can golf that down somewhat

--Damian

ruby -F, -pane'$F[5]="new" if 2..1876;$_=$F*","'

 

[l v]

Perl one liner for completeness:

perl -F, -lane '$F[6] = "new" if 2..1876; print join ",", @F' filename

I'm sure others in clpm can golf that down somewhat

--Damian

ruby -F, -pane'$F[5]="new" if 2..1876;$_=$F*","'

What version of Perl are you using? I can not find any Perl
documentation regarding "ruby" on my systems.

C:\>perldoc ruby
No documentation found for "ruby".

C:\>perldoc -f ruby
No documentation for perl function `ruby' found


Both are true for ActiveState Perl 5.6.1 build 631 and AIX 5.8.0


Len

 

[rashidaq]

Its actually record(db) file separated with commas
I used the awk script given by you guys

awk -F, 'NR>3&&NR<=7{$2="new_string"}1' file > newfile

I was wondering rather "> newfile" can I use sed to
edit the file.

the PERL stuff went over my head, but I bought the
perl book and I will open that book today.


thank you everybody for your help

Rashid

 

[Ed Morton]

Its actually record(db) file separated with commas
I used the awk script given by you guys

awk -F, 'NR>3&&NR<=7{$2="new_string"}1' file > newfile

Why NR<=7 instead of NR<8?

I was wondering rather "> newfile" can I use sed to
edit the file.

You mean edit the file in-line without using a tmp file? GNU sed can do
that with it's "-i" option, and "ed" can do it by default, but in either
case you still have that pesky field identification issue. You can get
round that by using an RE like this one which replaces the second field
("old") with the word "new":

$ echo "pre old post" | sed
's/\([^[:space:]]*[[:space:]]*\)[^[:space:]]*/\1new/'
pre new post

If you need it in some other field, you can specify a repetition count
for the number of fields to skip, e.g.:

$ echo "f1 f2 f3 f4 f5 f6" | sed
's/\(\([^[:space:]]*[[:space:]]*\)\{2\}\)[^[:space:]]*/\1new/'
f1 f2 new f4 f5 f6
$ echo "f1 f2 f3 f4 f5 f6" | sed
's/\(\([^[:space:]]*[[:space:]]*\)\{4\}\)[^[:space:]]*/\1new/'
f1 f2 f3 f4 new f6

You'll need to throw in an extra pattern if you want to accomodate white
space at the start of a line.

Regards,

Ed.

 

[Darren Dunham]

Or even...

perl -F, -ane '$F[5] =~ s/bob/sue/ if 6 .. 1876 ;print join(",",@F);'

If you want to get cryptic, you can save a few characters:

perl -F'/(,)/' -ane '$F[10] =~ s/bob/sue/ if 6 .. 1876; print @F'

That might even run faster because it avoids the join().

Ah, that made me think that doing $,="," might help. It would probably
aid clarity, but it doesn't seem to be actually shorter for any
construction of mine. (Also, I'd have either do it in a BEGIN block or
run it every time through the loop. The latter would work fine, but it
would annoy me.)

 

[Damian James]

Or even...

perl -F, -ane '$F[5] =~ s/bob/sue/ if 6 .. 1876 ;print join(",",@F);'

If you want to get cryptic, you can save a few characters:

perl -F'/(,)/' -ane '$F[10] =~ s/bob/sue/ if 6 .. 1876; print @F'

That might even run faster because it avoids the join().

Ah, that made me think that doing $,="," might help. It would probably
aid clarity, but it doesn't seem to be actually shorter for any
construction of mine. (Also, I'd have either do it in a BEGIN block or
run it every time through the loop. The latter would work fine, but it
would annoy me.)

*scratches head*

(I note that I introduced an off-by-one error cross thread by
equating awk's $6 with $F[6] instead of $F[5]).

Anyhow, with $, set:

perl -F, -lane '$,=",";$F[5] = "new" if 2..1876; print @F'

So yeah, it takes more characters, especially if you wanted a BEGIN block.
Similarly with $".

NB, the -l permits changing $F[-1] without needing to think about
line endings, not that that was required, but it seemed like the OP
wished to change arbitrary elements.

Likewise, I understood the OP intended to replace the whole element,
not a substring of it (the various awk solutions made this assumption).

So how about:

perl -F, -ape 's/$F[5]/new/ if 2..1876'

That breaks if $F[5] is a substring of an element to its left, of course.

--Damian

 

[William James]

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

if done in PERL easily then I have to learn that too.

thanks in advance
Rashid

ruby -F, -pane'$F[5]="new" if 2..7;$_=$F*","'

 

[rashidaq]

thanks for the sed script.

I have also tried the RUBY stuff in my cygwin and it worked.
This RUBY must be new, never heard of it.

How popular is it now as compared to Java, Perl or Python

I have taken a class in Java, its good but ..

But for my work working as telecom engr working on solaris system
most of the time, I think Ruby fits.
I dont know much about it.
Just downloaded ruby editor from FORGE site today.

thanks
Rashid

I have file which is separated by commas.
This is like csv file, actually a database which
has 10 to 15 fields separated by commas.

I can get a print of field number 6 awk on a file which has fields
separated by commas
awk -F, '{print $6}' file
this prints number 6 field only.

Now how do I substitute a certain field with another word/string on
certain line range.

I have tried the vi editor
I have manage to append line #6 to #1876 to the end of lines
here is what I do
:2,1876s/$/stringtobeAppended/g and it works but

now how do I replace in the middle like field number 6 separated by
commas
on certain line range.

if done in PERL easily then I have to learn that too.

thanks in advance
Rashid

ruby -F, -pane'$F[5]="new" if 2..7;$_=$F*","'

 

[Enrique Perez-Terron]

thanks for the sed script.

I have also tried the RUBY stuff in my cygwin and it worked.
This RUBY must be new, never heard of it.

Ruby's inventor named it Ruby thinking that was a suitable name
for a language that wanted to become the successor of Pe(a)rl.

How popular is it now as compared to Java, Perl or Python

I have not statistics, but I believe it still lives pretty much
in the shadow of these. When Perl appeared, it was like the
answer to everybody's frustrations. It had everything that
the day's scripting languges had been insisting on not having
for many years. When Ruby appeared, Perl was there, and it worked.

For a long time, Perl had CPAN, an enormous internet archive of
modules that would install themselves (or that Perl would
install) *correctly* with a single command that was (is) the same
on all architectures.

Only quite recently, I believe, has Ruby got that kind of
infrastructure.

I don't know why python got so much wind in its sails. I never
had the occasion to learn Ruby or Python well enough to judge
their relative merits. To my still rather superficial judgement
they have much in common, and seem to have been inpired by
much of the same theories. Both are very clean, uncluttered,
and rich in similar ways. Yet Python does not seem to have the
same advantage when it comes to one-liners.

I have taken a class in Java, its good but ..


But for my work working as telecom engr working on solaris system
most of the time, I think Ruby fits.
I dont know much about it.
Just downloaded ruby editor from FORGE site today.

-Enrique

 

[Mark Clements]

[follow-ups trimmed]

thanks for the sed script.

I have also tried the RUBY stuff in my cygwin and it worked.
This RUBY must be new, never heard of it.

OK - you have never heard of it. This puzzles me because later you say...

How popular is it now as compared to Java, Perl or Python

I have taken a class in Java, its good but ..

But for my work working as telecom engr working on solaris system
most of the time, I think Ruby fits.

You've never heard of it but you think it fits? Am not arguing for or
against the utility of Ruby for your problem domain, but am interested
in your logic.

I dont know much about it.

But it's a good fit, right?

puzzled,

Mark

 

[William James]

thanks for the sed script.

I have also tried the RUBY stuff in my cygwin and it worked.
This RUBY must be new, never heard of it.

How popular is it now as compared to Java, Perl or Python

I have taken a class in Java, its good but ..

But for my work working as telecom engr working on solaris system
most of the time, I think Ruby fits.
I dont know much about it.
Just downloaded ruby editor from FORGE site today.

Go to comp.lang.ruby and see the action.

By the way, my Ruby solution was 1 character too long; it could
have been:

ruby -F, -pae'$F[5]="new" if 2..7;$_=$F*","' file