3  Emmy-viewers

This namespace discusses Clay’s support for Emmy-viewers.

(ns clay-book.emmy-viewers
  (:require
   [scicloj.kindly.v4.kind :as kind]
   [emmy.env :as e :refer :all #_[D square cube tanh cos sin up down]]
   [emmy.viewer :as ev]
   [emmy.mafs :as mafs]
   [emmy.mathbox.plot :as plot]
   [emmy.leva :as leva]))

3.1 Usage

Here, we will not explain the full usage of Emmy-viewers. It is recommended to look into the project’ docs.

In Clay, forms generated by emmy-viewers are recognized and displayed accordingly.

(mafs/of-x e/sin {:color :blue})

3.2 A few detials behind the scenes

In the example above, we used emmy-viewers to generate a Clojurescript expression that can be interpreted as a Reagent component. Here is the actual expression:

(kind/pprint
 (mafs/of-x e/sin))

(reagent.core/with-let
 [G__84727 (js/Function. "y0001" "  return Math.sin(y0001);")]
 [mafs.plot/OfX {:y G__84727}])

By default, it is inferred to be of :kind/emmy-viewers, and is handle accordingly.

Equivalently, we could also handle it more explicitly with :kind/reagent:

(kind/reagent
 [`(fn []
     ~(ev/expand (mafs/of-x e/sin)))]
 {:html/deps [:emmy-viewers]})

3.3 More examples

(ev/with-let [!phase [0 0]]
  (let [shifted (ev/with-params {:atom !phase :params [0]}
                  (fn [shift]
                    (fn [x]
                      (((cube D) tanh) (e/- x shift)))))]
    (mafs/mafs
     {:height 400}
     (mafs/cartesian)
     (mafs/of-x shifted)
     (mafs/movable-point
      {:atom !phase :constrain "horizontal"})
     (mafs/inequality
      {:y {:<= shifted :> cos} :color :blue}))))

Try moving the pink mark. 👆

source: notebooks/clay_book/emmy_viewers.clj