Extend plot functionality (#3)

* Add fill_between

* Add semilogy, semilogx, loglog plot functions

examples/pyplot.ml

@@ -14,6 +14,8 @@ let () =
   Pyplot.grid true;
   Pyplot.plot ~color:Red ~xs ys1;
   Pyplot.plot ~color:Green ~linestyle:Dotted ~linewidth:2. ~xs ys2;
+  Pyplot.fill_between ~alpha:0.3
+    xs ys1 (Array.create ~len:(Array.length ys1) 0.);
   Pyplot.legend ~labels:[|"$y=\\sin(x/20)$"; "$y=\\cos(x/12)$"|] ();
   Mpl.savefig "test.png";
   let data = Mpl.plot_data `png in

src/matplotlib/mpl.ml

@@ -164,7 +164,7 @@ end
 
 let float_array_to_python xs = Py.List.of_array_map Py.Float.of_float xs
 
-let plot p ?label ?color ?linewidth ?linestyle ?xs ys =
+let call_plot_func p func ?label ?color ?linewidth ?linestyle ?xs ys =
   let keywords =
     List.filter_opt
       [ Option.map color ~f:(fun color -> "color", Color.to_pyobject color)
@@ -178,7 +178,34 @@ let plot p ?label ?color ?linewidth ?linestyle ?xs ys =
     | Some xs -> [| float_array_to_python xs; float_array_to_python ys |]
     | None -> [| float_array_to_python ys |]
   in
-  ignore (Py.Module.get_function_with_keywords p "plot" args keywords)
+  let func_name = match func with
+  | `plot -> "plot"
+  | `semilogy -> "semilogy"
+  | `semilogx -> "semilogx"
+  | `loglog -> "loglog"
+  in
+  ignore (Py.Module.get_function_with_keywords p func_name args keywords)
+
+let plot p ?label ?color ?linewidth ?linestyle ?xs ys =
+  call_plot_func p `plot ?label ?color ?linewidth ?linestyle ?xs ys
+
+let semilogy p ?label ?color ?linewidth ?linestyle ?xs ys =
+  call_plot_func p `semilogy ?label ?color ?linewidth ?linestyle ?xs ys
+
+let semilogx p ?label ?color ?linewidth ?linestyle ?xs ys =
+  call_plot_func p `semilogx ?label ?color ?linewidth ?linestyle ?xs ys
+
+let loglog p ?label ?color ?linewidth ?linestyle ?xs ys =
+  call_plot_func p `loglog ?label ?color ?linewidth ?linestyle ?xs ys
+
+let fill_between p ?color ?alpha xs ys1 ys2 =
+  let keywords = List.filter_opt
+    [ Option.map color ~f:(fun color -> "color", Color.to_pyobject color)
+    ; Option.map alpha ~f:(fun alpha -> "alpha", Py.Float.of_float alpha)
+    ]
+  in
+  let args = Array.map [|xs; ys1; ys2|] float_array_to_python in
+  ignore (Py.Module.get_function_with_keywords p "fill_between" args keywords)
 
 let hist p ?label ?color ?bins ?orientation ?histtype ?xs ys =
   let keywords =

src/matplotlib/mpl.mli

@@ -115,6 +115,45 @@ val plot
   -> float array
   -> unit
 
+val semilogy
+  :  Py.Object.t
+  -> ?label:string
+  -> ?color:Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val semilogx
+  :  Py.Object.t
+  -> ?label:string
+  -> ?color:Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val loglog
+  :  Py.Object.t
+  -> ?label:string
+  -> ?color:Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val fill_between
+  : Py.Object.t
+  -> ?color:Color.t
+  -> ?alpha:float
+  -> float array
+  -> float array
+  -> float array
+  -> unit
+
 val hist
   :  Py.Object.t
   -> ?label:string

src/matplotlib/pyplot.ml

@@ -29,6 +29,22 @@ let plot ?label ?color ?linewidth ?linestyle ?xs ys =
   let p = Mpl.pyplot_module () in
   Mpl.plot p ?label ?color ?linewidth ?linestyle ?xs ys
 
+let semilogy ?label ?color ?linewidth ?linestyle ?xs ys =
+  let p = Mpl.pyplot_module () in
+  Mpl.semilogy p ?label ?color ?linewidth ?linestyle ?xs ys
+
+let semilogx ?label ?color ?linewidth ?linestyle ?xs ys =
+  let p = Mpl.pyplot_module () in
+  Mpl.semilogx p ?label ?color ?linewidth ?linestyle ?xs ys
+
+let loglog ?label ?color ?linewidth ?linestyle ?xs ys =
+  let p = Mpl.pyplot_module () in
+  Mpl.loglog p ?label ?color ?linewidth ?linestyle ?xs ys
+
+let fill_between ?color ?alpha xs ys1 ys2 =
+  let p = Mpl.pyplot_module () in
+  Mpl.fill_between p ?color ?alpha xs ys1 ys2
+
 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

src/matplotlib/pyplot.mli

@@ -14,6 +14,41 @@ val plot
   -> float array
   -> unit
 
+val semilogy
+  :  ?label:string
+  -> ?color:Mpl.Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Mpl.Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val semilogx
+  :  ?label:string
+  -> ?color:Mpl.Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Mpl.Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val loglog
+  :  ?label:string
+  -> ?color:Mpl.Color.t
+  -> ?linewidth:float
+  -> ?linestyle:Mpl.Linestyle.t
+  -> ?xs:float array
+  -> float array
+  -> unit
+
+val fill_between
+  : ?color:Mpl.Color.t
+  -> ?alpha:float
+  -> float array
+  -> float array
+  -> float array
+  -> unit
+
 val hist
   :  ?label:string
   -> ?color:Mpl.Color.t