Help with reading part of textfile into matrix

ruby-talk
1

Dear all,

I am new to Ruby and I'm looking for a way to use Ruby (1.8) to read a part of
a textfile into a matrix.

The textfile lokks like:

=== Confusion Matrix ===

     a b c <-- classified as
  7494 4044 100 | a = WEL
  2039 18691 11 | b = NIET
   707 293 441 | c = NOOIT

So what i want is that this matrix is read into a matrix variable in a ruby
program which I can use then to manipulate in every way I want.

Can someone help me with this?

I figured out that I could maybe use a regexp /\s*a\s*/ to search for the line
with a b c
Then I skip that line and start to read the following line position by position
into the first row of the 3-by-3 matrix.

How could this be done?

Thanks in advance,
Robert Gilaard

2

Confused? :wink:

$ cat confusion.rb
matrix =

DATA.each do | line |
  if /^((?:\s+(?:\d+))+)/ =~ line
    matrix << $1.split.map{|value| value.to_i}
  end
end

p matrix

__END__
     a b c <-- classified as
7494 4044 100 | a = WEL
2039 18691 11 | b = NIET
  707 293 441 | c = NOOIT

$ ruby confusion.rb
[[7494, 4044, 100], [2039, 18691, 11], [707, 293, 441]]

regards,

Brian Schröder

···

On 10/05/05, rgilaard@few.vu.nl <rgilaard@few.vu.nl> wrote:

Dear all,

I am new to Ruby and I'm looking for a way to use Ruby (1.8) to read a part of
a textfile into a matrix.

The textfile lokks like:

=== Confusion Matrix ===

     a b c <-- classified as
  7494 4044 100 | a = WEL
  2039 18691 11 | b = NIET
   707 293 441 | c = NOOIT

So what i want is that this matrix is read into a matrix variable in a ruby
program which I can use then to manipulate in every way I want.

Can someone help me with this?

I figured out that I could maybe use a regexp /\s*a\s*/ to search for the line
with a b c
Then I skip that line and start to read the following line position by position
into the first row of the 3-by-3 matrix.

How could this be done?

Thanks in advance,
Robert Gilaard

--
http://ruby.brian-schroeder.de/

multilingual _non rails_ ruby based vocabulary trainer:
http://www.vocabulaire.org/ | http://www.gloser.org/ | http://www.vokabeln.net/

3

Oof course I am confused a s a ruby newbie!!

However,
I've made this out of your post:
matrix =

DATA = File.new("testfile.txt", "r")
DATA.each do | line |
if /^((?:\s+(?:\d+))+)/ =~ line
matrix << $1.split.map{|value| value.to_i}
end
end

p matrix
puts matrix[2,2]
DATA.close

But this gives me as result
707
293
441

while I would expect 441.

What is going on?

Brgds
Robert

Quoting Brian Schröder <ruby.brian@gmail.com>:

···

On 10/05/05, rgilaard@few.vu.nl <rgilaard@few.vu.nl> wrote:
> Dear all,
>
> I am new to Ruby and I'm looking for a way to use Ruby (1.8) to read a part
of
> a textfile into a matrix.
>
> The textfile lokks like:
>
> === Confusion Matrix ===
>
> a b c <-- classified as
> 7494 4044 100 | a = WEL
> 2039 18691 11 | b = NIET
> 707 293 441 | c = NOOIT
>
> So what i want is that this matrix is read into a matrix variable in a
ruby
> program which I can use then to manipulate in every way I want.
>
> Can someone help me with this?
>
> I figured out that I could maybe use a regexp /\s*a\s*/ to search for the
line
> with a b c
> Then I skip that line and start to read the following line position by
position
> into the first row of the 3-by-3 matrix.
>
> How could this be done?
>
> Thanks in advance,
> Robert Gilaard
>

Confused? :wink:

$ cat confusion.rb
matrix =

DATA.each do | line |
  if /^((?:\s+(?:\d+))+)/ =~ line
    matrix << $1.split.map{|value| value.to_i}
  end
end

p matrix

__END__
     a b c <-- classified as
7494 4044 100 | a = WEL
2039 18691 11 | b = NIET
  707 293 441 | c = NOOIT

$ ruby confusion.rb
[[7494, 4044, 100], [2039, 18691, 11], [707, 293, 441]]

regards,

Brian Schröder

--
http://ruby.brian-schroeder.de/

multilingual _non rails_ ruby based vocabulary trainer:
http://www.vocabulaire.org/ | http://www.gloser.org/ |
http://www.vokabeln.net/

4

rgilaard@few.vu.nl wrote:

Oof course I am confused a s a ruby newbie!!

However,
I've made this out of your post:
matrix =

DATA = File.new("testfile.txt", "r")
DATA.each do | line |
if /^((?:\s+(?:\d+))+)/ =~ line
matrix << $1.split.map{|value| value.to_i}
end

p matrix
puts matrix[2,2]
DATA.close

But this gives me as result 707
293
441

while I would expect 441.

What is going on?

Here you would want 'puts matrix[2][2]'.

Your form actually returns a slice,
i.e. "starting from element 2, give
me 2 elements" (and there is only one).

Brgds
Robert

Quoting Brian Schröder <ruby.brian@gmail.com>:

Dear all,

I am new to Ruby and I'm looking for a way to use Ruby (1.8) to read a part

of

a textfile into a matrix.

The textfile lokks like:

=== Confusion Matrix ===

    a b c <-- classified as
7494 4044 100 | a = WEL
2039 18691 11 | b = NIET
  707 293 441 | c = NOOIT

So what i want is that this matrix is read into a matrix variable in a

ruby

program which I can use then to manipulate in every way I want.

Can someone help me with this?

I figured out that I could maybe use a regexp /\s*a\s*/ to search for the

line

with a b c
Then I skip that line and start to read the following line position by

position

into the first row of the 3-by-3 matrix.

How could this be done?

Thanks in advance,
Robert Gilaard

Confused? :wink:

$ cat confusion.rb matrix =

DATA.each do | line |
if /^((?:\s+(?:\d+))+)/ =~ line
   matrix << $1.split.map{|value| value.to_i}
end
end

p matrix

__END__
    a b c <-- classified as
7494 4044 100 | a = WEL
2039 18691 11 | b = NIET
707 293 441 | c = NOOIT

$ ruby confusion.rb [[7494, 4044, 100], [2039, 18691, 11], [707, 293, 441]]

regards,

Brian Schröder

--
http://ruby.brian-schroeder.de/

multilingual _non rails_ ruby based vocabulary trainer:
http://www.vocabulaire.org/ | http://www.gloser.org/ |
http://www.vokabeln.net/

E

···

On 10/05/05, rgilaard@few.vu.nl <rgilaard@few.vu.nl> wrote:

--
template<typename duck>
void quack(duck& d) { d.quack(); }