Re: help regarding extracting a particular value in a file


#1

Assuming that your data is in a file “data_to_split.txt” in the same
directory,
you can do this:

file_name=“data_to_split.txt”
data_array=IO.readlines(file_name) # reads content of file into an
Array (
each entry = one line)
only_second_entries=[]
data_array.each{|line|
only_second_entries<<(line.split(’,’)[1]) # note that indices start at
0 in
Ruby
}
p ‘only second entries contains’
p only_second_entries

If you have more complicated patterns that separate your data than just
a
comma,
you can also use split in conjunction with “regular expressions”.

      only_second_entries<<(line.split(/,/)[1])  # note that indices

start at 0 in Ruby

These “regular expressions” allow to search for things like “a comma and
then two small letters, followed by at least three numbers and then
anything but
“A””, so there is
room for arbitrary complexity …
Regular expressions are explained in detail here:

http://www.regular-expressions.info/
(http://www.regular-expressions.info/)

Best regards,

Axel


#2

Hi Nuralanur

Thanks for your reply and help.
My data.txt file contains data like

p1,p2,p3
c1,c2,c3

I did try your code.Its giving output
p2
c2

but i want to retrieve a single value like p2(2nd value of 1st row ) or
c3
(3rd value of 2nd row)only.

Thanks in advance
Tanushree