extract consecutive lines of data

[baptiste Auguié]

Hi,


A basic question: how to extract several consecutive lines of numbers
in a text file (example below) and assign them to some GSL::Matrix in
Ruby?

text file:

some lines of text ...
....
more text
below is the data to extract

1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4


some more text

from which i would like to create three vectors, a=[1, 4, 7, 23], b=
[2, 5, 8, 7.33-8], c=[3, 6, 9, 3.4]. The line numbers could be used
for indexing if that can help.

Many thanks,

baptiste

 

[Robert Dober]

Hi,


A basic question: how to extract several consecutive lines of numbers
in a text file (example below) and assign them to some GSL::Matrix in
Ruby?

text file:

some lines of text ...
....
more text
below is the data to extract

1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4


some more text

from which i would like to create three vectors, a=3D[1, 4, 7, 23], b=3D
[2, 5, 8, 7.33-8], c=3D[3, 6, 9, 3.4]. The line numbers could be used
for indexing if that can help.

p DATA.readlines.map{ |line| line.chomp.split }.transpose
__END__
1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4

Many thanks,

baptiste

HTH
Robert



--=20
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/

 

[baptiste Auguié]

Hi,

Thanks for the hints, however it doesn't quite work for me yet. I tried,

p DATA.readlines.map{ |line| line.chomp.split }.transpose
__END__
1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4

which produces a nice matrix as suggested, but I can't figure how to =20
read that data from an external file rather than below this "__END__" =20=

thing ; nor can I see how to deal with the extra text lines above and =20=

below the data. This is actually the main problem, as I would =20
otherwise go for

require("rbgsl")
a, b, c =3D GSL::Vector.filescan(filename)

Thanks again,

baptiste

Hi,


A basic question: how to extract several consecutive lines of numbers
in a text file (example below) and assign them to some GSL::Matrix in
Ruby?

text file:

some lines of text ...
....
more text
below is the data to extract

1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4


some more text

from which i would like to create three vectors, a=3D[1, 4, 7, 23], = b=3D
[2, 5, 8, 7.33-8], c=3D[3, 6, 9, 3.4]. The line numbers could be used
for indexing if that can help.

p DATA.readlines.map{ |line| line.chomp.split }.transpose
__END__
1 2 3
4 5 6
7 8 9
23 7.3e-8 3.4

Many thanks,

baptiste

HTH
Robert



--=20
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/

_____________________________

Baptiste Augui=E9

Physics Department
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag
http://projects.ex.ac.uk/atto
______________________________

 

[MonkeeSage]

def input_matrix(file)
File.open(file) { |f|
f.readlines.collect { |line|
line = line.chomp
if line.empty?
then nil
else line.split
end
}.compact.transpose
}
end

p input_matrix(ARGV[0])

^ Composes matrix from first file given on command line, ignoring
blank lines in file.

Regards,
Jordan

 

[baptiste Auguié]

Thanks, this didn't work either (the data file contains lines of text =20=

before and after the data).
I've eventually figured a way playing with different bits of code I =20
found:

# extract space separated numbers from lines 5 to 9 in 'data.txt',
# ignoring header and footer text lines

current =3D []

File.foreach('data.txt') do |line|
if ($. =3D=3D 5) .. ($. =3D=3D 9)
current << line.scan(/\S+/).map! {|x| x.to_f}
end
end
p current

Best wishes,

baptiste

def input_matrix(file)
File.open(file) { |f|
f.readlines.collect { |line|
line =3D line.chomp
if line.empty?
then nil
else line.split
end
}.compact.transpose
}
end

p input_matrix(ARGV[0])

^ Composes matrix from first file given on command line, ignoring
blank lines in file.

Regards,
Jordan

_____________________________

Baptiste Augui=E9

Physics Department
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag
http://projects.ex.ac.uk/atto
______________________________

 

[Robert Dober]

Thanks, this didn't work either (the data file contains lines of text
before and after the data).

grep is your friend

508/8 > cat data.txt && cat detect.rb && ruby detect.rb data.txt
1 2 3
Some text
4 5 6
more text
7 8 9
42 42 42
23 7.3e-8 3.4
#!/usr/local/bin/ruby
# vim: sw=3D2 ts=3D2 ft=3Druby expandtab tw=3D0 nu syn:

p ARGF.readlines.grep(/^\s*[\.\d]/).map{ |line| line.chomp.split }.transpos=
e

[["1", "4", "7", ".42", "23"], ["2", "5", "8", "42", "7.3e-8"], ["3",
"6", "9", "42", "3.4"]]

BTW don't forget to tell us the mark you got

R.
--=20
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/

 

[MonkeeSage]

# vim: sw=2 ts=2 ft=ruby expandtab tw=0 nu syn:

Happiness! Another vim user.

Regards,
Jordan

 

[baptiste Auguié]

Thanks, this is exactly what i was looking for: I just never find my =20
way in these regular expressions, not to mention how to adapt it in =20
Ruby code!

grep is your friend

508/8 > cat data.txt && cat detect.rb && ruby detect.rb data.txt
1 2 3
Some text
4 5 6
more text
7 8 9
.42 42 42
23 7.3e-8 3.4
#!/usr/local/bin/ruby
# vim: sw=3D2 ts=3D2 ft=3Druby expandtab tw=3D0 nu syn:

p ARGF.readlines.grep(/^\s*[\.\d]/).map{ |line| =20
line.chomp.split }.transpose

[["1", "4", "7", ".42", "23"], ["2", "5", "8", "42", "7.3e-8"], ["3",
"6", "9", "42", "3.4"]]

BTW don't forget to tell us the mark you got

do you get a mark for a PhD? I can only tell you the imaginary part =20
is gonna be negative, in terms of propagation constant.


_____________________________

Baptiste Augui=E9

Physics Department
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag
http://projects.ex.ac.uk/atto
______________________________

 

[Robert Dober]

Thanks, this is exactly what i was looking for: I just never find my
way in these regular expressions, not to mention how to adapt it in
Ruby code!

grep is your friend

508/8 > cat data.txt && cat detect.rb && ruby detect.rb data.txt
1 2 3
Some text
4 5 6
more text
7 8 9
.42 42 42
23 7.3e-8 3.4
#!/usr/local/bin/ruby
# vim: sw=3D2 ts=3D2 ft=3Druby expandtab tw=3D0 nu syn:

p ARGF.readlines.grep(/^\s*[\.\d]/).map{ |line|
line.chomp.split }.transpose

[["1", "4", "7", ".42", "23"], ["2", "5", "8", "42", "7.3e-8"], ["3",
"6", "9", "42", "3.4"]]

BTW don't forget to tell us the mark you got

do you get a mark for a PhD? I can only tell you the imaginary part
is gonna be negative, in terms of propagation constant.

Well in that case you just state the sources just kidding, I am
aware that Ruby is only doing some "low" stuff, but still glad you use
it as a tool, and concerning your PhD
"bonne chance".

R.

_____________________________

Baptiste Augui=E9

Physics Department
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag
http://projects.ex.ac.uk/atto
______________________________

--=20
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/