Sum Keyword Values in Array of Maps Clojure

Hi! Here I shows you How to Sum Keyword Values in Array of Maps in Clojure Programming Language.

And to easily achieve this outcome I make use of the reduce and map Functions.

Especially relevant: we can easily getting this Result because in Clojure you can use Keywords as Functions.

1. Sum Keyword Values in Array of Maps

   So, for instance, if we have a most populated Cities Array of Maps like:

   (def cities
   [
   {:name "Tokyo" :pop 37.5}
   {:name "Delhi" :pop 28.5}
   {:name "Shangai" :pop 25.5}
   {:name "Sao Paulo" :pop 21.5}
   {:name "Mexico City" :pop 21.5}
   {:name "Cairo" :pop 20}
   ])

   We apply “reduce” with “+” on a “map” Keyword on cities like:

   (reduce + (map :pop cities))
   => 154.5