Reg Ex Help Required

ruby-talk
1

Hi,

Please help me with regular expression.

str = "abc = 100.300"

i want to write a regular xpression for getting the value after =, i.e.
100.300, i mean reg ex should return value after =

Please help.

Thanks
Saurabh

···

--
Posted via http://www.ruby-forum.com/.

2

ruby-1.8.7-p334 :006 > str = "abc = 100.300"
=> "abc = 100.300"
ruby-1.8.7-p334 :007 > /= (.*)/.match(str)[0]
=> "= 100.300"

···

On Wed, Aug 10, 2011 at 2:20 PM, saurabh a. <saurabh_anand2002@yahoo.com>wrote:

Hi,

Please help me with regular expression.

str = "abc = 100.300"

i want to write a regular xpression for getting the value after =, i.e.
100.300, i mean reg ex should return value after =

Please help.

Thanks
Saurabh

--
Posted via http://www.ruby-forum.com/\.

3

Might I suggest an alternative to regex?

irb(main):003:0> str.split(/ = /)
=> ["abc", "100.300"]
irb(main):004:0> str.split(/ = /)[1]
=> "100.300"
irb(main):005:0>

Regards,
Chris White
http://www.twitter.com/cwgem

···

On Aug 10, 2011, at 11:20 AM, saurabh a. wrote:

Hi,

Please help me with regular expression.

str = "abc = 100.300"

i want to write a regular xpression for getting the value after =, i.e.
100.300, i mean reg ex should return value after =

4

sorry, should be

ruby-1.8.7-p334 :006 > str = "abc = 100.300"
=> "abc = 100.300"
ruby-1.8.7-p334 :008 > /= (.*)/.match(str)[1]
=> "100.300"

···

On Wed, Aug 10, 2011 at 2:26 PM, Ian M. Asaff <ian.asaff@gmail.com> wrote:

ruby-1.8.7-p334 :006 > str = "abc = 100.300"
=> "abc = 100.300"
ruby-1.8.7-p334 :007 > /= (.*)/.match(str)[0]
=> "= 100.300"

On Wed, Aug 10, 2011 at 2:20 PM, saurabh a. <saurabh_anand2002@yahoo.com>wrote:

Hi,

Please help me with regular expression.

str = "abc = 100.300"

i want to write a regular xpression for getting the value after =, i.e.
100.300, i mean reg ex should return value after =

Please help.

Thanks
Saurabh

--
Posted via http://www.ruby-forum.com/\.

5

alternatively you could make the two inputs variables and the output you are
trying to recieve a variable as well that way you would never have to worry
about regexing anything. You would simply reference the variable . . . You
can of course create a class as well . . .

puts "First Number"
r = gets.chomp
puts "Second Number"
p = gets.chomp
x = p * r
puts x

class Someclass
def initialize (First Number, Second Number)
@First Number = First Number
@Second Number = Second Number
end
end

Calc = Someclass.new(0,1)
x = calc.first * calc.last

Of course if you're working with floats or strings back and forth just add
the to_f or to_s. I haven't worked on ruby in a while but maybe this will
help you spawn some ideas.

···

On Wed, Aug 10, 2011 at 1:30 PM, Chris White <cwprogram@live.com> wrote:

On Aug 10, 2011, at 11:20 AM, saurabh a. wrote:

> Hi,
>
> Please help me with regular expression.
>
> str = "abc = 100.300"
>
> i want to write a regular xpression for getting the value after =, i.e.
> 100.300, i mean reg ex should return value after =

Might I suggest an alternative to regex?

irb(main):003:0> str.split(/ = /)
=> ["abc", "100.300"]
irb(main):004:0> str.split(/ = /)[1]
=> "100.300"
irb(main):005:0>

Regards,
Chris White
http://www.twitter.com/cwgem

6

I'd use split as well, but I'd probably do it like this:

str = "abc = 100.300"
variable, value = str.split('=', 2).map(&:strip)
variable # => "abc"
value # => "100.300"

···

On Wed, Aug 10, 2011 at 1:30 PM, Chris White <cwprogram@live.com> wrote:

On Aug 10, 2011, at 11:20 AM, saurabh a. wrote:

> Hi,
>
> Please help me with regular expression.
>
> str = "abc = 100.300"
>
> i want to write a regular xpression for getting the value after =, i.e.
> 100.300, i mean reg ex should return value after =

Might I suggest an alternative to regex?

irb(main):003:0> str.split(/ = /)
=> ["abc", "100.300"]
irb(main):004:0> str.split(/ = /)[1]
=> "100.300"
irb(main):005:0>

Regards,
Chris White
http://www.twitter.com/cwgem

7

Um, no, why would you need a class to store two numbers? I'd go with
Chris's split approach. Unless what you really want is to match the
number, then you do need regex and an example one would be /\d+\.\d+/
.

···

2011/8/10, Daniel Navarro <djonavarro@gmail.com>:

alternatively you could make the two inputs variables and the output you are
trying to recieve a variable as well that way you would never have to worry
about regexing anything. You would simply reference the variable . . . You
can of course create a class as well . . .

puts "First Number"
r = gets.chomp
puts "Second Number"
p = gets.chomp
x = p * r
puts x

class Someclass
def initialize (First Number, Second Number)
@First Number = First Number
@Second Number = Second Number
end
end

Calc = Someclass.new(0,1)
x = calc.first * calc.last

Of course if you're working with floats or strings back and forth just add
the to_f or to_s. I haven't worked on ruby in a while but maybe this will
help you spawn some ideas.

On Wed, Aug 10, 2011 at 1:30 PM, Chris White <cwprogram@live.com> wrote:

On Aug 10, 2011, at 11:20 AM, saurabh a. wrote:

> Hi,
>
> Please help me with regular expression.
>
> str = "abc = 100.300"
>
> i want to write a regular xpression for getting the value after =, i.e.
> 100.300, i mean reg ex should return value after =

Might I suggest an alternative to regex?

irb(main):003:0> str.split(/ = /)
=> ["abc", "100.300"]
irb(main):004:0> str.split(/ = /)[1]
=> "100.300"
irb(main):005:0>

Regards,
Chris White
http://www.twitter.com/cwgem

--
-- Matma Rex

8

I'd probably use a regex for the split sequence rather than a literal to
account for variations in whitespace, rather than a map:

    variable, value = str.split(/\s*=\s*/, 2)

. . . but either way works.

···

On Thu, Aug 11, 2011 at 07:34:54AM +0900, Josh Cheek wrote:

I'd use split as well, but I'd probably do it like this:

str = "abc = 100.300"
variable, value = str.split('=', 2).map(&:strip)
variable # => "abc"
value # => "100.300"

--
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]

9

It seems to me that there could be whitespace on either end, ie

"
def whatever
  var = 123
end
"

This shows a very common example of leading whitespace, so I thought using
strip would be better.

···

On Wed, Aug 10, 2011 at 7:44 PM, Chad Perrin <code@apotheon.net> wrote:

On Thu, Aug 11, 2011 at 07:34:54AM +0900, Josh Cheek wrote:
>
> I'd use split as well, but I'd probably do it like this:
>
> str = "abc = 100.300"
> variable, value = str.split('=', 2).map(&:strip)
> variable # => "abc"
> value # => "100.300"

I'd probably use a regex for the split sequence rather than a literal to
account for variations in whitespace, rather than a map:

   variable, value = str.split(/\s*=\s*/, 2)

. . . but either way works.

--
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]

10

Although, I suppose you could make the argument that an actual parser would
be best.

···

On Wed, Aug 10, 2011 at 8:15 PM, Josh Cheek <josh.cheek@gmail.com> wrote:

On Wed, Aug 10, 2011 at 7:44 PM, Chad Perrin <code@apotheon.net> wrote:

On Thu, Aug 11, 2011 at 07:34:54AM +0900, Josh Cheek wrote:
>
> I'd use split as well, but I'd probably do it like this:
>
> str = "abc = 100.300"
> variable, value = str.split('=', 2).map(&:strip)
> variable # => "abc"
> value # => "100.300"

I'd probably use a regex for the split sequence rather than a literal to
account for variations in whitespace, rather than a map:

   variable, value = str.split(/\s*=\s*/, 2)

. . . but either way works.

--
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]

It seems to me that there could be whitespace on either end, ie

"
def whatever
  var = 123
end
"

This shows a very common example of leading whitespace, so I thought using
strip would be better.

11

Did I miss the part where someone said that the "var" part is actually
something the code should preserve separately?

···

On Thu, Aug 11, 2011 at 10:15:57AM +0900, Josh Cheek wrote:

It seems to me that there could be whitespace on either end, ie

"
def whatever
  var = 123
end
"

This shows a very common example of leading whitespace, so I thought
using strip would be better.

--
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]