Examples for how to use Ruby's Array#each_with_object, Array#reduce (thanks to #ruby's Radar and baweaver)

reduce.rb

src = [{foo: 1.2, bar: 2.3}, {foo: 3.2, bar: 3.0}]
src.each_with_object({foo: [], bar: []}) { |data, acc| acc[:foo] << data[:foo]; acc[:bar] << data[:bar] }
# => {:foo=>[1.2, 3.2], :bar=>[2.3, 3.0]}

[{foo: 1.2, bar: 2.3}, {foo: 3.2, bar: 3.0}].reduce { |a,b| a.merge(b) { |_,o,n| Array(o) << n } }
# => {:foo=>[1.2, 3.2], :bar=>[2.3, 3.0]}