Text lines manipulation

Ruby
1

have a set of lines like shown below:
#set1
1-3
3-5
6-7
#set2
20-23
450-550
#set3
1-50
20-56

The idea is to read each of the lines associated with each set and do
some manipulation?

any easy way of doing this?

Thanks

2

Hi,

Am Montag, 31. Aug 2009, 18:46:53 +0900 schrieb George G.:

20-56

The idea is to read each of the lines associated with each set and do
some manipulation?

Untested:

file.each_line { |l|
l.chomp!
case l
when /^#/ then set = $’
else
do_sth_with set, l
end
}

Bertram

3

Thanks Betram

This seems to work for me,
dont know whether its efficient or there is a better implementation

file.each_line do |line|
line.chomp!
case line
when /^>/ then set = $’
puts set
else

   re1='(\\d+)'  # Integer Number 1
   re2='(-)'  # Any Single Character 1
   re3='(\\d+)'  # Integer Number 2

 re=(re1+re2+re3)
 m=Regexp.new(re,Regexp::IGNORECASE);
   if m.match(line)
      int1 = m.match(line)[1];
      c1   = m.match(line)[2];
      int2 = m.match(line)[3];
      puts int1<< c1 << int2
  end
end

end

Bertram S. wrote:

Hi,

Am Montag, 31. Aug 2009, 18:46:53 +0900 schrieb George G.:

20-56

The idea is to read each of the lines associated with each set and do
some manipulation?

Untested:

file.each_line { |l|
l.chomp!
case l
when /^#/ then set = $’
else
do_sth_with set, l
end
}

Bertram

4

Hi –

On Mon, 31 Aug 2009, Bertram S. wrote:

Hi,

Am Montag, 31. Aug 2009, 20:33:19 +0900 schrieb George G.:

 m=Regexp.new(re,Regexp::IGNORECASE);
   if m.match(line)
      int1 = m.match(line)[1];
      c1   = m.match(line)[2];
      int2 = m.match(line)[3];
      puts int1<< c1 << int2
  end

To the OP: definitely lose the semi-colons :slight_smile:

if line =~ /(\d+)(-)(\d+)/i then
int1 = $1
c1 = $2
int2 = $3
puts int1 + c1 + int2
end

This is for the not faint-hearted:

int1, c1, int2 = *$~.captures

It’s a little less formidable without the *, which should be OK. A
mixed solution:

int1, c1, int2 = $1, $2, $3

or use Regexp#match and save the match explicitly.

match = m.match(line)

if match
int1, c1, int2 = match.captures
end

or similar.

David

–
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5

Hi,

Am Montag, 31. Aug 2009, 23:42:43 +0900 schrieb David A. Black:

On Mon, 31 Aug 2009, Bertram S. wrote:

int1, c1, int2 = *$~.captures

It’s a little less formidable without the *, which should be OK. A
mixed solution:

int1, c1, int2 = $1, $2, $3

There’s so much more nice things you can do. I cannot hold it back
any more.

h = {}
…
h[ set] ||= []
h[ set].push int1.to_i…int2.to_i

And so on. Isn’t it sweet?

Bertram

6

Hi,

Am Montag, 31. Aug 2009, 20:33:19 +0900 schrieb George G.:

 m=Regexp.new(re,Regexp::IGNORECASE);
   if m.match(line)
      int1 = m.match(line)[1];
      c1   = m.match(line)[2];
      int2 = m.match(line)[3];
      puts int1<< c1 << int2
  end

After `m.match(line)’ the match is stored in the $~ global
variable. You don’t need to execute it three more times.

$~[1] is equivalent to $1.

The <<' operator modifieds the stringint1’. Better is here the
operator `+’.

It’s sure a matter of taste but in general shorter code is easier
to read.

if line =~ /(\d+)(-)(\d+)/i then
int1 = $1
c1 = $2
int2 = $3
puts int1 + c1 + int2
end

This is for the not faint-hearted:

int1, c1, int2 = *$~.captures

Bertram