Group_by is the command your looking for Tommy. Running that on your array
gets your this:
autos = [{:id => 1, :name => 'toyota'}, {:id => 2, :name => 'ford' }, {:id
=> 3, :name => 'toyota'} ]
autos.group_by {|h| h[:name]}
#=> {"toyota"=>[{:name=>"toyota", :id=>1}, {:name=>"toyota", :id=>3}],
"ford"=>[{:name=>"ford", :id=>2}]}
you can then call .values on your hash to get the arrays like your looking
for (similar to Jordan's collect statement, but much faster for large sets)
It is worth noting that group_by is added to Rails, and does not exist in
core Ruby. It is defined in activesupport in the file
rails/activesupport/lib/active_support/core_ext/enumerable.rb
its definition (in case your in Rubyland and not Railsville)
def group_by
inject({}) do |groups, element|
(groups[yield(element)] ||= []) << element
groups
end
end
Rob
On Wed, Mar 26, 2008 at 12:31 PM, Jordan Fowler <[EMAIL PROTECTED]> wrote:
> autos = [{:id => 1, :name => 'toyota'}, {:id => 2, :name => 'ford' }, {:id
> => 3, :name => 'toyota'} ]
> autos.group_by {|h| h[:name]}.collect {|k,v| v} #=> [[{:name=>"toyota",
> :id=>1}, {:name=>"toyota", :id=>3}], [{:name=>"ford", :id=>2}]]
>
>
>
> On Wed, Mar 26, 2008 at 12:12 PM, tommy <[EMAIL PROTECTED]> wrote:
>
> >
> > hey guys,
> > got an array question:
> >
> > class Autos
> > with a variable name
> >
> > I have an array of Autos. I want to split this array into chunks of
> > arrays grouped by name.
> >
> > ie, Autos = [{id:1, name:toyota}, {id:2, name:ford}, {id:3,
> > name:toyota} ]
> > would create two arrays in a super array
> > [ [{id:1, name:toyota},{id:3, name:toyota}] , [{id:2, name:ford:}] ]
> >
> > i have the unique list of names.
> >
> > I was roughly thinking of sorting the array by name and finding the
> > first occurrence of each name and doing a slice.
> >
> > Is there a faster approach?
> >
> >
>
>
> --
> Jordan A. Fowler
> 2621 First Ave Apt 5
> San Diego, CA 92103
> E-mail: [EMAIL PROTECTED]
> Website: http://www.jordanfowler.com
> Phone: 406.546.8055
>
> >
>
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