Greetings,
I have a CSV file with three fields. eg.
a1,b1,c1 a2,b2,c2 ....
I wanted the output to be: b1,c1,a1 b2,c2,a2 ....
the command cut -d, -f2,3,1 <file>
returns
a1,b1,c1
cut -d, -f2,3 <file>
works as advertised.
Is it specific to linux?
In that case how do I go about swapping two columns? I do not think a gazzillion byte gui is required.
The file size is about 43Megs.
any ideas?
Rajagopal Swaminathan wrote:
Greetings,
I have a CSV file with three fields. eg.
a1,b1,c1 a2,b2,c2 ....
I wanted the output to be: b1,c1,a1 b2,c2,a2 ....
the command cut -d, -f2,3,1 <file>
returns
a1,b1,c1
cut -d, -f2,3 <file>
works as advertised.
Is it specific to linux?
In that case how do I go about swapping two columns? I do not think a gazzillion byte gui is required.
The file size is about 43Megs.
I've never been that good with cut. I'm going to see the author, Dave Ihnat this weekend, who sometimes shows up here... but in the meantime, you might use awk 'BEGIN {FS=",";}{print $2 "," $3 "," $1;}' infile
mark
Greetings,
On Wed, Aug 29, 2012 at 1:36 AM, m.roth@5-cent.us wrote:
I've never been that good with cut. I'm going to see the author, Dave Ihnat this weekend, who sometimes shows up here... but in the meantime, you might use awk 'BEGIN {FS=",";}{print $2 "," $3 "," $1;}' infile
I tried it on an xp box with GnuWin32 binaries. It barked some error showing the single quote.
I will try on a centos box later (<grin>which I am silently injecting [installing] into that env after handwaving the xp</grin>).
Le mer. 29 août 2012 01:44:48 CEST, Rajagopal Swaminathan a écrit:
Greetings,
On Wed, Aug 29, 2012 at 1:36 AM, m.roth@5-cent.us wrote:
I've never been that good with cut. I'm going to see the author, Dave Ihnat this weekend, who sometimes shows up here... but in the meantime, you might use awk 'BEGIN {FS=",";}{print $2 "," $3 "," $1;}' infile
I tried it on an xp box with GnuWin32 binaries. It barked some error showing the single quote.
I will try on a centos box later (<grin>which I am silently injecting [installing] into that env after handwaving the xp</grin>).
You can also try with bash : while IFS="," read A B C ; do echo "$B,$C,$A" ; done < infile
Regards,
On 28.8.2012 21:59, Rajagopal Swaminathan wrote:
Greetings,
I have a CSV file with three fields. eg.
a1,b1,c1 a2,b2,c2 ....
I wanted the output to be: b1,c1,a1 b2,c2,a2 ....
the command cut -d, -f2,3,1 <file>
returns
a1,b1,c1
cut cuts out, that what it does. I think it works exactly as advertised. On my system the manpage says
...snip Selected input is written in the same order that it is read, and is written exactly once snap...
Is it specific to linux?
No!
On Wed, Aug 29, 2012 at 2:15 AM, Markus Falb markus.falb@fasel.at wrote:
On 28.8.2012 21:59, Rajagopal Swaminathan wrote:
cut cuts out, that what it does. I think it works exactly as advertised. On my system the manpage says
...snip Selected input is written in the same order that it is read, and is written exactly once snap...
See below
Is it specific to linux?
No!
I would think, yes.
From: http://www.unix.com/unix-dummies-questions-answers/117504-question-cut-comma...
[quote] 08-22-2009 Scott's Avatar Scott Scott is offline Forum Staff Administrator Join Date: Jun 2009 Location: Switzerland - ZH Posts: 5,632 Thanks: 136 Thanked 596 Times in 515 Posts
In AIX (for example) if you said
Code: echo 1,2,3,4,5 | cut -d, -f3,1,5
you would get output as 3,1,5
But the cut command in Linux behaves differently.
From the man page:
Quote: Selected input is written in the same order that it is read, and is written exactly once.
Which I think is poor. I can't see any way to do what you want with cut.
[unquote]
Thanks for everybody who pitched in
Any the issue got transformed into something else altogether.... (PHB, vlookup 'experts' and the such for time being)
On Wed, Aug 29, 2012 at 10:43 AM, Rajagopal Swaminathan raju.rajsand@gmail.com wrote:
But the cut command in Linux behaves differently.
From the man page:
Quote: Selected input is written in the same order that it is read, and is written exactly once.
Which I think is poor. I can't see any way to do what you want with cut.
[unquote]
If you are willing to use tmp files you can: cut -d, -f1 <input >tmp1 cut -d, -f2 <input >tmp2 cut -d, -f3 <input >tmp3
paste -d, tmp1 tmp3 tmp2 >file_I_wanted rm tmp1 tmp2 tmp3
There's probably a clever way to do this with tee and fifos to handle unlimited stream sizes but I'm too lazy to work it out.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
On 29.8.2012 17:43, Rajagopal Swaminathan wrote:
On Wed, Aug 29, 2012 at 2:15 AM, Markus Falb markus.falb@fasel.at wrote:
On 28.8.2012 21:59, Rajagopal Swaminathan wrote:
cut cuts out, that what it does. I think it works exactly as advertised. On my system the manpage says
...snip Selected input is written in the same order that it is read, and is written exactly once snap...
See below
Is it specific to linux?
No!
I would think, yes.
On a OS-X, and thats non arguably not linux-ish (means gnu-ish) but bsd-ish
$ echo 1,2,3,4,5 | cut -d, -f3,1,5 1,3,5
So it's definitely not specific to linux.
From: http://www.unix.com/unix-dummies-questions-answers/117504-question-cut-comma...
[quote] ... In AIX (for example) if you said
Code: echo 1,2,3,4,5 | cut -d, -f3,1,5
you would get output as 3,1,5
I tend to think that AIX is not posix compliant, then. http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cut.html
The behaviour of cut makes sense to me, actually. I remember one of the UNIX paradigms and thats "do only one thing but do it good"
However, I realize that I do not suggest a better way to do what you want to do, but I do not think I have to, there were so many hints in this thread pointing you to awk and I remember actually one shell only example. - -- Kind Regards, Markus Falb
On Wed, Aug 29, 2012 at 11:52 AM, Markus Falb markus.falb@fasel.at wrote:
From: http://www.unix.com/unix-dummies-questions-answers/117504-question-cut-comma...
[quote] ... In AIX (for example) if you said
Code: echo 1,2,3,4,5 | cut -d, -f3,1,5
you would get output as 3,1,5
I tend to think that AIX is not posix compliant, then. http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cut.html
The behaviour of cut makes sense to me, actually. I remember one of the UNIX paradigms and thats "do only one thing but do it good"
So sed with a regexp? sed -e 's/([^,]*),([^,]*),([^,]*)/\1\3\2/'
On 08/29/2012 09:52 AM, Markus Falb wrote:
From:
http://www.unix.com/unix-dummies-questions-answers/117504-question-cut-comma... [quote] ... In AIX (for example) if you said Code: echo 1,2,3,4,5 | cut -d, -f3,1,5 you would get output as 3,1,5
I tend to think that AIX is not posix compliant, then. http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cut.html
Well, according to that document, AIX's cut seems to behave as POSIX and Scott (on unix.com) is simply wrong about the application's behavior.
On Wed, Aug 29, 2012 at 12:25:29PM -0700, Gordon Messmer wrote:
On 08/29/2012 09:52 AM, Markus Falb wrote:
From:
http://www.unix.com/unix-dummies-questions-answers/117504-question-cut-comma... [quote] ... In AIX (for example) if you said Code: echo 1,2,3,4,5 | cut -d, -f3,1,5 you would get output as 3,1,5
I tend to think that AIX is not posix compliant, then. http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cut.html
Well, according to that document, AIX's cut seems to behave as POSIX and Scott (on unix.com) is simply wrong about the application's behavior.
No need to guess about what AIX does: $ uname -svr AIX 1 6 $ oslevel 6.1.0.0 $ echo 1,2,3,4,5 | cut -d, -f3,1,5 1,3,5 $
On Tue, Aug 28, 2012 at 2:59 PM, Rajagopal Swaminathan raju.rajsand@gmail.com wrote:
I have a CSV file with three fields. eg.
a1,b1,c1 a2,b2,c2 ....
I wanted the output to be: b1,c1,a1 b2,c2,a2 ....
the command cut -d, -f2,3,1 <file>
returns
a1,b1,c1
cut -d, -f2,3 <file>
works as advertised.
Is it specific to linux?
In that case how do I go about swapping two columns? I do not think a gazzillion byte gui is required.
The file size is about 43Megs.
any ideas?
If you are sure that the fields will never contain commas, there are any number of ways to split lines into variables in any number of scripting languages including bash. However, if the input is 'generic csv' that is allowed to have quotes around fields with embedded commas it can be hard to parse. I'd recommend perl with the Text::CSV module so you don't have to deal with parsing yourself.
On Wed, Aug 29, 2012 at 01:29:05AM +0530, Rajagopal Swaminathan wrote:
a1,b1,c1 a2,b2,c2
cut -d, -f2,3,1 <file>
Will not work. The "-f" flag specifies what columns; not the order. Everyone makes that mistake once :-)
In that case how do I go about swapping two columns? I do not think a gazzillion byte gui is required.
Use "awk" awk -F, '{print $2 "," $3 "," $1}'
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