Convert String "1;2;3;4;5;" to Array [1, 2, 3, 4, 5]

Ruby
1

I’m trying to convert a String of numbers that are separated by
semicolons to an Array—totally for fun, to stretch my ruby
understanding, fyi.

I use the Array in a while loop which does work when the Array looks
like = [1,2,3,4,5,…]—so that part is working. But I want to use ruby
to
convert a String = “1;2;3;4;5;6;7;8;9;10” into an Array [1,2,3,4,5,…]
so
that I can use these values.

I’ve tried many a method, but can’t seem to get the desired result; I’ve
tried gsub(/;/, “,”), eval (), and others.

##########

raw_data = “1;2;3;4;5;6;7;8;9;10”
data = raw_data.split(/;/) #but this gives [“1”, “2”, “3”, “4”, “5”,
“6”, “7”, “8”, “9”, “10”], not [1, 2, 3,…]

#data = [1,2,3,4,5,6,7,8,9,10,11,12] # this is the desired result

boundary = 1
ending_boundary = 13
interval = (ending_boundary - boundary)/3

while boundary < ending_boundary
print "For the class #{boundary} to #{boundary + interval}, "
print "the group is: "
puts data.select{ |x| x >= boundary && x < (boundary + interval)
}.size
print data.select{ |x| x >= boundary && x < (boundary + interval)
}.join(’ ')
boundary = boundary + interval #increase the boundary to the next
class
print “.\n”
end

2

I’ve tried many a method, but can’t seem to get the desired result; I’ve
tried gsub(/;/, “,”), eval (), and others.

##########

raw_data = “1;2;3;4;5;6;7;8;9;10”
data = raw_data.split(/;/) #but this gives [“1”, “2”, “3”, “4”, “5”,
“6”, “7”, “8”, “9”, “10”], not [1, 2, 3,…]

This is the right track, you just need to then convert each string to
a number, e.g.

raw_data.split(";").map { |raw| raw.to_i }

3

you mean something like this?

“1;2;3;4;5;6;7;8;9;10”.split(’;’).inject([]) { |a,i| a << i.to_i }
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

looking below, where do 11, 12 come from in the desired result?

raw_data = “1;2;3;4;5;6;7;8;9;10”
data = raw_data.split(/;/) #but this gives [“1”, “2”, “3”, “4”, “5”,
“6”, “7”, “8”, “9”, “10”], not [1, 2, 3,…]

#data = [1,2,3,4,5,6,7,8,9,10,11,12] # this is the desired result
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

4

Thanks to both. I’m reading up on these methods you’ve supplied at
RDoc Documentation. It looks like the .map method is a
synonym for .collect. I’ll read up on .inject next.

you mean something like this?

“1;2;3;4;5;6;7;8;9;10”.split(‘;’).inject([]) { |a,i| a << i.to_i }
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Yes. In fact, both of these work—liking ruby’s flexibility here.

#data = raw_data.split(/;/).map { |raw| raw.to_f}
#data = raw_data.split(/;/).inject([]) { |a,i| a << i.to_f }

looking below, where do 11, 12 come from in the desired result? my
inconsistency.

Thomas

5

Yep.

–sent from myu droid. typoos courtesy of droid’s crappy keyboarsd

6

Ian M. Asaff wrote in post #971169:

you mean something like this?
“1;2;3;4;5;6;7;8;9;10”.split(’;’).inject([]) { |a,i| a << i.to_i }
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Ok, I’ve read the page on .inject, but do have a question on your
solution. I’m interested in the [] where I read an initial value may be
supplied in .inject([]). Is the [] initializing an empty array to which
the accumulator, a, will populate?

7

I would avoid the inject solution because it’s cumbersome and isn’t as
easy
to understand; map is pretty much to-the-point and doesn’t have this
weird
empty-array accumulator. The inject solution is just reinventing the map
wheel.

8

How about this?

eval(“[” + “1;2;3”.gsub(/;/,‘,’) + “]”)
=> [1,2,3]

Masa

2010/12/29 Adam P. [email protected]:

9

On Tue, Dec 28, 2010 at 5:19 PM, Thomas T. [email protected] wrote:

Yes. In fact, both of these work—liking ruby’s flexibility here.

#data = raw_data.split(/;/).map { |raw| raw.to_f}
#data = raw_data.split(/;/).inject([]) { |a,i| a << i.to_f }

Go with map, this is its raison d’etre.

10

Thank you all for your assistance. Calling the .methods on a string like
I had was rather overwhelming, and many of the RDoc definitions are
still opaque to me.