Add scatter plots.

examples/fig.ml

@@ -37,3 +37,28 @@ let () =
  right_graph ax2;
  Fig.suptitle fig "the figure suptitle";
  Mpl.show ()
+
+let () =
+ let fig, ax = Fig.create_with_ax () in
+ let xys1 =
+ Array.init 1000 ~f:(fun i ->
+ let f = Float.of_int i /. 20. in
+ Float.sin f, Float.cos f)
+ in
+ let xys2 =
+ Array.init 1000 ~f:(fun i ->
+ let f = Float.of_int i /. 20. in
+ let rho = 1. +. Float.cos f in
+ rho *. Float.sin f, rho *. Float.cos f)
+ in
+ let xys3 =
+ Array.init 1000 ~f:(fun i ->
+ let f = Float.of_int i /. 20. in
+ let rho = 1.5 +. 0.2 *. Float.cos (5. *. f) in
+ rho *. Float.sin f, rho *. Float.cos f)
+ in
+ Ax.scatter ax ~s:4. ~c:Green ~marker:'o' ~alpha:0.5 xys1;
+ Ax.scatter ax ~s:4. ~c:Red ~marker:'X' xys2;
+ Ax.scatter ax ~c:Blue ~marker:'*' xys3;
+ Fig.suptitle fig "...scatter...";
+ Mpl.show ()

src/matplotlib/fig_ax.ml

@@ -19,6 +19,15 @@ module Ax = struct
  let set_ylabel t label =
  ignore (t.&("set_ylabel")[| Py.String.of_string label |])
 
+ let set_aspect t ~aspect =
+ let aspect =
+ match aspect with
+ | `auto -> Py.String.of_string "auto"
+ | `equal -> Py.String.of_string "equal"
+ | `f f -> Py.Float.of_float f
+ in
+ ignore (t.&("set_aspect")[| aspect |])
+
  let grid t ?which ?axis b =
  let keywords =
  let b = Some ("b", Py.Bool.of_bool b) in
@@ -72,6 +81,7 @@ module Ax = struct
 
  let plot = Mpl.plot
  let hist = Mpl.hist
+ let scatter = Mpl.scatter
 end
 
 module Fig = struct

src/matplotlib/fig_ax.mli

@@ -6,6 +6,7 @@ module Ax : sig
  val set_ylim : t -> bottom:float -> top:float -> unit
  val set_xlabel : t -> string -> unit
  val set_ylabel : t -> string -> unit
+ val set_aspect : t -> aspect:[`auto|`equal|`f of float] -> unit
  val grid : t -> ?which:[`major|`minor|`both] -> ?axis:[`both|`x|`y] -> bool -> unit
  val legend
  : ?loc:
@@ -43,6 +44,19 @@ module Ax : sig
  -> ?xs:float array list
  -> float array
  -> unit
+
+ val scatter
+ : t
+ -> ?s:float
+ -> ?c:Mpl.Color.t
+ (* Possible markers:
+ 'o', 'v', '^', '<', '>', '8', 's', 'p', '*', 'h', 'H', 'D', 'd', 'P', 'X'
+ *)
+ -> ?marker:char
+ -> ?alpha:float
+ -> ?linewidths:float
+ -> (float * float) array
+ -> unit
 end
 
 module Fig : sig

src/matplotlib/mpl.ml

@@ -181,3 +181,17 @@ let hist p ?label ?color ?bins ?orientation ?histtype ?xs ys =
  | None -> [| float_array_to_python ys |]
  in
  ignore (Py.Module.get_function_with_keywords p "hist" args keywords)
+
+let scatter p ?s ?c ?marker ?alpha ?linewidths xys =
+ let keywords =
+ List.filter_opt
+ [ Option.map c ~f:(fun c -> "c", Color.to_pyobject c)
+ ; Option.map s ~f:(fun s -> "s", Py.Float.of_float s)
+ ; Option.map marker ~f:(fun m -> "marker", String.of_char m |> Py.String.of_string)
+ ; Option.map alpha ~f:(fun a -> "alpha", Py.Float.of_float a)
+ ; Option.map linewidths ~f:(fun l -> "linewidths", Py.Float.of_float l)
+ ]
+ in
+ let xs = Py.List.of_array_map (fun (x, _) -> Py.Float.of_float x) xys in
+ let ys = Py.List.of_array_map (fun (_, y) -> Py.Float.of_float y) xys in
+ ignore (Py.Module.get_function_with_keywords p "scatter" [| xs; ys |] keywords)

src/matplotlib/mpl.mli

@@ -86,7 +86,7 @@ val plot
  -> unit
 
 val hist
- : Py.Object.t
+ :  Py.Object.t
  -> ?label:string
  -> ?color:Color.t
  -> ?bins:int
@@ -95,3 +95,16 @@ val hist
  -> ?xs:float array list
  -> float array
  -> unit
+
+val scatter
+ : Py.Object.t
+ -> ?s:float
+ -> ?c:Color.t
+ (* Possible markers:
+ 'o', 'v', '^', '<', '>', '8', 's', 'p', '*', 'h', 'H', 'D', 'd', 'P', 'X'
+ *)
+ -> ?marker:char
+ -> ?alpha:float
+ -> ?linewidths:float
+ -> (float * float) array
+ -> unit

src/matplotlib/pyplot.ml

@@ -32,3 +32,7 @@ let plot ?label ?color ?linewidth ?linestyle ?xs ys =
 let hist ?label ?color ?bins ?orientation ?histtype ?xs ys =
  let p = Mpl.pyplot_module () in
  Mpl.hist p ?label ?color ?bins ?orientation ?histtype ?xs ys
+
+let scatter ?s ?c ?marker ?alpha ?linewidths xys =
+ let p = Mpl.pyplot_module () in
+ Mpl.scatter p ?s ?c ?marker ?alpha ?linewidths xys

src/matplotlib/pyplot.mli

@@ -23,3 +23,15 @@ val hist
  -> ?xs:float array list
  -> float array
  -> unit
+
+val scatter
+ : ?s:float
+ -> ?c:Mpl.Color.t
+ (* Possible markers:
+ 'o', 'v', '^', '<', '>', '8', 's', 'p', '*', 'h', 'H', 'D', 'd', 'P', 'X'
+ *)
+ -> ?marker:char
+ -> ?alpha:float
+ -> ?linewidths:float
+ -> (float * float) array
+ -> unit