(defmulti set-background-default 
"

  Examples:
    (use '(incanter core stats charts datasets))

    (doto (histogram (sample-normal 1000) :title (str :Test-Tittle))
      set-theme-bw
      view)

 
    (doto (histogram (sample-normal 1000))
      set-background-default
      (add-histogram (sample-normal 1000 :mean 1))
      view)


    (doto (scatter-plot :speed :dist :data (get-dataset :cars))
      set-theme-bw
      view)

    (doto (scatter-plot :speed :dist :data (get-dataset :cars))
      set-theme-bw
      (set-stroke :dash 5)
      (add-points (plus ($ :speed (get-dataset :cars)) 5) (plus ($ :dist (get-dataset :cars)) 10))
      view)

    (doto (scatter-plot :speed :dist :data (get-dataset :cars))
      set-background-default
      (set-stroke :dash 5)
      (add-function sin 0 25)
      view)


    (doto (xy-plot :speed :dist :data (get-dataset :cars) :legend true)
      set-background-default
      view)


    (doto (scatter-plot :speed :dist :data (get-dataset :cars))
      set-background-default
      view)

   
    (doto (box-plot (sample-gamma 1000 :shape 1 :rate 2)
                    :legend true)
      view set-background-default
      (add-box-plot (sample-gamma 1000 :shape 2 :rate 2))
      (add-box-plot (sample-gamma 1000 :shape 3 :rate 2)))


    (doto (bar-chart [:a :b :c] [10 20 30] :legend true)
      view
      set-background-default
      (add-categories [:a :b :c] [5 25 40]))
  

    (doto (line-chart [:a :b :c] [10 20 30] :legend true)
      view
      set-background-default
      (add-categories [:a :b :c] [5 25 40]))
 
    ;; time-series-plot
    (def epoch 0)
    (defn num-years-to-milliseconds [x]
      (* 365 24 60 60 1000 x))
    (def dates (map num-years-to-milliseconds (range 100)))
    (def chart1 (time-series-plot dates (range 100)))
    (def cw1 (view chart1))
    (add-lines chart1 dates (mult 1/2 (range 100)))

    (def chart2 (time-series-plot (take 10 dates) (mult 1/2 (range 10))))
    (def cw2 (view chart2))


"
(fn [chart] (type (.getPlot chart))))