I would like to extract the 3 columns of data for several consecutive lines (say, from angle = 158 to 165). These values should be stored in some array or vector. How can I do that in Ruby?
# Make an array of arrays of numbers
# based on scanning for non-whitespace characters
# (all strings will show up as 0.0)
values = IO.readlines( 'input.dat' ).map{ |line|
line.scan( /\S+/ ).map{ |str| str.to_f }
}
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
Many ways to approach it of course.
You could use CSV or FasterCSV since your data file is lines (rows) with columns separated by tabs or spaces.
CSV or FasterCSV might be more useful to do other things also with the data file.
but you can also just read the first 3 or 4 bytes of each line to find the lines you want.
···
On Oct 17, 2007, at 11:03 AM, baptiste Auguié wrote:
Hello,
This is a basic question, as I'm very new to Ruby. I have a text file 'input.dat' containing the following data and text:
I would like to extract the 3 columns of data for several consecutive lines (say, from angle = 158 to 165). These values should be stored in some array or vector. How can I do that in Ruby?
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
I would like to extract the 3 columns of data for several consecutive lines
(say, from angle = 158 to 165). These values should be stored in some array
or vector. How can I do that in Ruby?
Anybody considered ranges?
r = 158..165
file.each { |l|
ang, val1, val2 = l.split.map { |x| Float x }
r === ang and do_sth_with val1, val2
}
r = 158..165
file.each { |l|
ang, val1, val2 = l.split.map { |x| Float x }
case ang
when r then do_sth_with val1, val2
end
}
Does anybody remember flip-flops?
file.each { |l|
ang, val1, val2 = l.split.map { |x| Float x }
iang = ang.floor
if (iang==158)..(iang==165) then
do_sth_with val1, val2
end
}
The floor call is not actually beautiful here but always
keep in mind equality shouldn't be tested for floats.
Flip-flops need equality.
Bertram
···
Am Donnerstag, 18. Okt 2007, 01:03:21 +0900 schrieb baptiste Auguié:
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
# Make an array of arrays of numbers
# based on scanning for non-whitespace characters
# (all strings will show up as 0.0)
values = IO.readlines( 'input.dat' ).map{ |line|
line.scan( /\S+/ ).map{ |str| str.to_f }
}
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
# Make an array of arrays of numbers
# based on scanning for non-whitespace characters
# (all strings will show up as 0.0)
values = IO.readlines( 'input.dat' ).map{ |line|
line.scan( /\S+/ ).map{ |str| str.to_f }
}
On Oct 17, 11:03 am, baptiste Auguié <ba...@exeter.ac.uk> wrote:
> Hello,
>
> This is a basic question, as I'm very new to Ruby. I have a text file
> 'input.dat' containing the following data and text:
>
> > some text
> > some text...
>
> > angle value1 value2
>
> > 156.00 3.3688E-03 1.7040E-03
> > 157.00 3.2919E-03 1.7118E-03
> > 158.00 3.2140E-03 1.7190E-03
> > 159.00 3.1354E-03 1.7258E-03
> > 160.00 3.0560E-03 1.7320E-03
> > 161.00 2.9760E-03 1.7378E-03
> > 162.00 2.8956E-03 1.7431E-03
> > 163.00 2.8148E-03 1.7479E-03
> > 164.00 2.7338E-03 1.7523E-03
> > 165.00 2.6526E-03 1.7562E-03
> > 166.00 2.5714E-03 1.7597E-03
> > 167.00 2.4902E-03 1.7628E-03
>
> I would like to extract the 3 columns of data for several consecutive
> lines (say, from angle = 158 to 165). These values should be stored
> in some array or vector. How can I do that in Ruby?
>
> Many thanks,
>
> baptiste
p IO.readlines( 'input.dat').grep( /^\d/ ).
map{|s| s.strip.split.map{|x| x.to_f}}.select{|a|
a.first.between?(158,165) }
Please pardon my perverse prolixity. I threw in a "strip" even though
my subconscious told me it was superfluous.
p IO.readlines( 'input.dat').grep( /^\d/ ).
map{|s| s.split.map{|x| x.to_f}}.select{|a|
a.first.between?(158,165) }
I would like to extract the 3 columns of data for several consecutive
lines (say, from angle = 158 to 165). These values should be stored
in some array or vector. How can I do that in Ruby?
# Make an array of arrays of numbers
# based on scanning for non-whitespace characters
# (all strings will show up as 0.0)
values = IO.readlines( 'input.dat' ).map{ |line|
line.scan( /\S+/ ).map{ |str| str.to_f }
}
(Assuming the > at the beginning isn't really part of it -- otherwise
">%f%f%f".)
I'm not entering the speed contest but scanf might be nice for the
conversions.
David
···
On Thu, 18 Oct 2007, Phrogz wrote:
On Oct 17, 10:03 am, baptiste Auguié <ba...@exeter.ac.uk> wrote:
--
Upcoming training from Ruby Power and Light, LLC:
* Intro to Ruby on Rails, Edison, NJ, October 23-26
* Advancing with Rails, Edison, NJ, November 6-9
Both taught by David A. Black.
See http://www.rubypal.com for more info!
>> I would like to extract the 3 columns of data for several consecutive
>> lines (say, from angle = 158 to 165). These values should be stored
>> in some array or vector. How can I do that in Ruby?
> # Make an array of arrays of numbers
> # based on scanning for non-whitespace characters
> # (all strings will show up as 0.0)
> values = IO.readlines( 'input.dat' ).map{ |line|
> line.scan( /\S+/ ).map{ |str| str.to_f }
> }
If you can't guess that "> " isn't actually part of the data,
you could have deduced it from the fact that the o.p. gave
Gavin's program the seal of approval. Gavin's program won't
work if the lines start with "> ". Your program won't work
since the lines don't start with "> ".
stop = '> 166.00'
results =
get_line = false
File.foreach("data.txt") do |line|
test_field = line[0, start.length]
if test_field == start
get_line = true
end
if get_line
results << line.split()[1..-1].map{|str| str.to_f}
if test_field == stop
break
end
end
end
Have you thought about doing all of your programming in COBOL?
···
On Oct 17, 12:32 pm, 7stud -- <bbxx789_0...@yahoo.com> wrote:
> On Oct 17, 10:03 am, baptiste Augui? <ba...@exeter.ac.uk> wrote:
but scanf might be nice for the