Hello, Can someone help me to write a Ruby one-liner to remove all the files except one in a list of files? I have a list of pages of an original PDF. Each page has been converted to a PNG file. They're each numbered with an underscore and a number at their end. filename_1.png filename_2.png filename_3.png ... I need to basically delete all of the files except for the first one, the one with the "_1" suffix at the end. Can I do that wiith a one-liner? Thanks, Peter
on 2013-01-08 21:48
on 2013-01-08 23:04
Peter Bailey wrote in post #1091502: > Hello, > Can someone help me to write a Ruby one-liner to remove all the files > except one in a list of files? I have a list of pages of an original > PDF. Each page has been converted to a PNG file. They're each numbered > with an underscore and a number at their end. > > filename_1.png > filename_2.png > filename_3.png > ... > > I need to basically delete all of the files except for the first one, > the one with the "_1" suffix at the end. Can I do that wiith a > one-liner? > > Thanks, > Peter Test this: ruby -e "Dir.foreach('C:/Directory_with_png/') {|file| File.delete(file) unless (file.==('.')) || (file.==('..') || (file.==('filename_1.png'))" Kind regards.
on 2013-01-09 00:29
> > I need to basically delete all of the files except for the first one, > the one with the "_1" suffix at the end. Can I do that wiith a > one-liner? > > Thanks, > Peter > Hi, This should work ruby -e "Dir.glob('*_*.png')[1..-1].each { |fn| File.delete fn}" Best regards Kim
on 2013-01-09 13:08
Kim Pedersen wrote in post #1091524: >> >> I need to basically delete all of the files except for the first one, >> the one with the "_1" suffix at the end. Can I do that wiith a >> one-liner? >> >> Thanks, >> Peter >> > > Hi, > > This should work > > ruby -e "Dir.glob('*_*.png')[1..-1].each { |fn| File.delete fn}" > > Best regards > Kim Thank you very much, Kim. It's a big help. Cheers.
on 2013-01-09 16:10
On Tue, Jan 8, 2013 at 9:48 PM, Peter Bailey <lists@ruby-forum.com> wrote: > > I need to basically delete all of the files except for the first one, > the one with the "_1" suffix at the end. Can I do that wiith a > one-liner? ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' Kind regards robert
on 2013-01-09 16:13
Robert Klemme wrote in post #1091597: > On Tue, Jan 8, 2013 at 9:48 PM, Peter Bailey <lists@ruby-forum.com> > wrote: >> >> I need to basically delete all of the files except for the first one, >> the one with the "_1" suffix at the end. Can I do that wiith a >> one-liner? > > ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' > > Kind regards > > robert Thanks, Robert.
on 2013-01-09 16:15
Kim Pedersen wrote in post #1091524: >> >> I need to basically delete all of the files except for the first one, >> the one with the "_1" suffix at the end. Can I do that wiith a >> one-liner? >> >> Thanks, >> Peter >> > > Hi, > > This should work > > ruby -e "Dir.glob('*_*.png')[1..-1].each { |fn| File.delete fn}" > > Best regards > Kim Kim, I'd like to ask you about [1..-1]. I've never seen that before. Is that what's selecting all the files except the first one? -Peter
on 2013-01-09 16:23
about Array#[]: [1,2,3,4,5][1..-1] #=> [2,3,4,5] about Dir.glob(): you need to be careful, because the array is unsorted
on 2013-01-09 16:49
On Wed, Jan 9, 2013 at 4:09 PM, Robert Klemme <shortcutter@googlemail.com> wrote: >> ... >> >> I need to basically delete all of the files except for the first one, >> the one with the "_1" suffix at the end. Can I do that wiith a >> one-liner? > > ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' Careful, as this skips also filename_11.png, filename_21.png, etc. Building on this: ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' Jesus.
on 2013-01-09 16:56
On Wed, Jan 9, 2013 at 4:48 PM, Jess Gabriel y Galn <jgabrielygalan@gmail.com> wrote: > On Wed, Jan 9, 2013 at 4:09 PM, Robert Klemme > <shortcutter@googlemail.com> wrote: >> ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' > > Careful, as this skips also filename_11.png, filename_21.png, etc. > Building on this: > > ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' +1 I wasn't aware that there could be larger numbers. Thank you for the correction! Cheers robert
on 2013-01-09 17:00
"Jesús Gabriel y Galán" <jgabrielygalan@gmail.com> wrote in post #1091607: > On Wed, Jan 9, 2013 at 4:09 PM, Robert Klemme > <shortcutter@googlemail.com> wrote: >>> ... >>> >>> I need to basically delete all of the files except for the first one, >>> the one with the "_1" suffix at the end. Can I do that wiith a >>> one-liner? >> >> ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' > > Careful, as this skips also filename_11.png, filename_21.png, etc. > Building on this: > > ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' > > Jesus. Excellent. Thanks. Hans is right, though. Dir.glob is unsorted. Is that a problem here?
on 2013-01-09 17:14
On Wed, Jan 9, 2013 at 5:00 PM, Peter Bailey <lists@ruby-forum.com> wrote: >>> ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' >> >> Careful, as this skips also filename_11.png, filename_21.png, etc. >> Building on this: >> >> ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' >> >> Jesus. > > Excellent. Thanks. Hans is right, though. Dir.glob is unsorted. Is that > a problem here? No, because here we are using the glob facility to do all the filtering. In the other solution, there was the array returned from the glob that was being filtered, and so the order was important for the solution that removed the first entry in the array. Jesus.
on 2013-01-09 17:23
"Jesús Gabriel y Galán" <jgabrielygalan@gmail.com> wrote in post #1091613: > On Wed, Jan 9, 2013 at 5:00 PM, Peter Bailey <lists@ruby-forum.com> > wrote: >>>> ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' >>> >>> Careful, as this skips also filename_11.png, filename_21.png, etc. >>> Building on this: >>> >>> ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' >>> >>> Jesus. >> >> Excellent. Thanks. Hans is right, though. Dir.glob is unsorted. Is that >> a problem here? > > No, because here we are using the glob facility to do all the > filtering. In the other solution, there was the array returned from > the glob that was being filtered, and so the order was important for > the solution that removed the first entry in the array. > > Jesus. Beautiful. Thanks a lot.
on 2013-01-10 01:08
Peter Bailey wrote in post #1091614: > "Jesús Gabriel y Galán" <jgabrielygalan@gmail.com> wrote in post > #1091613: >> On Wed, Jan 9, 2013 at 5:00 PM, Peter Bailey <lists@ruby-forum.com> >> wrote: >>>>> ruby -r pathname -e 'Pathname.glob("*[^1].png").each(&:delete)' >>>> >>>> Careful, as this skips also filename_11.png, filename_21.png, etc. >>>> Building on this: >>>> >>>> ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' >>>> >>>> Jesus. >>> >>> Excellent. Thanks. Hans is right, though. Dir.glob is unsorted. Is that >>> a problem here? >> >> No, because here we are using the glob facility to do all the >> filtering. In the other solution, there was the array returned from >> the glob that was being filtered, and so the order was important for >> the solution that removed the first entry in the array. >> >> Jesus. > > Beautiful. Thanks a lot. This is what I'm getting. I'm sure i'm missing something simple. ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' -e:1: syntax error, unexpected $end, expecting ')'
on 2013-01-10 08:12
On Thu, Jan 10, 2013 at 1:09 AM, Peter Bailey <lists@ruby-forum.com> wrote: >>>>> ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' >>> >>> Jesus. >> >> Beautiful. Thanks a lot. > > This is what I'm getting. I'm sure i'm missing something simple. > > ruby -r pathname -e 'Pathname.glob("*_{[^1],??}.png").each(&:delete)' > -e:1: syntax error, unexpected $end, expecting ')' Any chance you are using Ruby 1.8*? If so I suggest to upgrade to 1.9*. Kind regards robert
on 2013-01-10 10:24
On 01/08/2013 05:04 PM, Damián M. González wrote: >> ... > ruby -e "Dir.foreach('C:/Directory_with_png/') {|file| File.delete(file) > unless (file.==('.')) || (file.==('..') || (file.==('filename_1.png'))" > > Kind regards. > There's certainly many ways to do this, but globing will ignore the dot dirs, and is a bit shorter. File.delete *Dir['*.png'].reject {|f| f =~ /_1\.png$/ }
on 2013-01-10 12:58
Brian D. B. wrote in post #1091712: > On 01/08/2013 05:04 PM, Damián M. González wrote: >>> ... >> ruby -e "Dir.foreach('C:/Directory_with_png/') {|file| File.delete(file) >> unless (file.==('.')) || (file.==('..') || (file.==('filename_1.png'))" >> >> Kind regards. >> > > There's certainly many ways to do this, but globing will ignore the dot > dirs, and is a bit shorter. > File.delete *Dir['*.png'].reject {|f| f =~ /_1\.png$/ } Thanks, Brian. But, even preceding this with "ruby -e" gives me nothing. Should I make this part of a script instead of it being a one-liner?
on 2013-01-11 11:12
On 01/10/2013 06:58 AM, Peter Bailey wrote: >> dirs, and is a bit shorter. >> File.delete *Dir['*.png'].reject {|f| f =~ /_1\.png$/ } > > Thanks, Brian. But, even preceding this with "ruby -e" gives me nothing. > Should I make this part of a script instead of it being a one-liner? > That's odd... Works for me under 1.8.7, 1.9.2 and 1.9.3. ruby -e "File.delete *Dir['*.png'].reject {|f| f=~ /_1\.png$/ }" There will be no output. It will just delete the files.
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