Spline curve

lib/matplotex.ex

@@ -2,6 +2,7 @@ defmodule Matplotex do
   @moduledoc """
   Module to generate a graph.
   """
+  alias Matplotex.Figure.Areal.Spline
   alias Matplotex.Figure.Areal.Histogram
   alias Matplotex.InputError
   alias Matplotex.Figure.Radial.Pie
@@ -33,6 +34,9 @@ defmodule Matplotex do
     |> BarChart.create({pos, values, width}, opts)
   end
 
+  @doc """
+  Creates a scatter plot based on the given data
+  """
   def scatter(stream, opts) when is_struct(stream, Stream) do
     Scatter.create(stream, opts)
   end
@@ -51,6 +55,9 @@ defmodule Matplotex do
     |> Scatter.create({x, y}, opts)
   end
 
+  @doc """
+  Creates a piec charts based on the size and opts
+  """
   def pie(sizes, opts \\ []) do
     Pie.create(%Figure{axes: %Pie{}}, sizes, opts)
   end
@@ -84,10 +91,26 @@ defmodule Matplotex do
     |> LinePlot.create({x, y}, opts)
   end
 
+  @doc """
+   Creates a histogram with given data and bins.
+
+   ## Examples
+
+       iex> Matplotex.hist([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 5)
+  """
+  def hist(data, bins), do: hist(data, bins, [])
+
   def hist(data, bins, opts) do
     Histogram.create(%Figure{axes: %Histogram{}}, {data, bins}, opts)
   end
 
+  def spline(x, y), do: spline(x, y, [])
+  def spline(x, y, opts), do: spline(%Figure{axes: %Spline{}}, x, y, opts)
+
+  def spline(%Figure{} = figure, x, y, opts) do
+    Spline.create(figure, {x, y}, opts)
+  end
+
   @doc """
   Sets X and Y labels for the graph with given font details
 

lib/matplotex/element.ex

@@ -1,8 +1,11 @@
 defmodule Matplotex.Element do
   @callback assemble(element :: struct()) :: String.t()
-  @callback flipy(element :: struct(), height :: number()) :: struct()
   def assemble(%module{} = element), do: module.assemble(element)
 
+  def to_pixel({x, y}) do
+    "#{to_pixel(x)},#{to_pixel(y)}"
+  end
+
   def to_pixel(inch) when is_number(inch), do: inch * 96
   def to_pixel(_), do: 0
 

lib/matplotex/element/circle.ex

@@ -32,8 +32,4 @@ defmodule Matplotex.Element.Circle do
   def get_cx(%{cx: x}), do: to_pixel(x)
   def get_cy(%{cy: y}), do: to_pixel(y)
   def get_r(%{r: r}), do: to_pixel(r)
-  @impl Element
-  def flipy(%__MODULE__{cy: y} = circle, height) do
-    %__MODULE__{circle | cy: height - y}
-  end
 end

lib/matplotex/element/label.ex

@@ -71,8 +71,4 @@ defmodule Matplotex.Element.Label do
   def get_y(%{y: y}), do: to_pixel(y)
   def get_width(%{width: width}), do: to_pixel(width)
   def get_height(%{height: height}), do: to_pixel(height)
-  @impl Element
-  def flipy(%__MODULE__{y: y} = label, height) do
-    %__MODULE__{label | y: height - y}
-  end
 end

lib/matplotex/element/legend.ex

@@ -30,11 +30,6 @@ defmodule Matplotex.Element.Legend do
     """
   end
 
-  @impl Element
-  def flipy(%__MODULE__{y: y} = legend, height) do
-    %__MODULE__{legend | y: height - y, label: Label.flipy(legend.label, height)}
-  end
-
   defp handle(%__MODULE__{handle: %handle_element{} = handle}) do
     handle_element.assemble(handle)
   end

lib/matplotex/element/line.ex

@@ -52,10 +52,6 @@ defmodule Matplotex.Element.Line do
   def get_x2(%{x2: x2}), do: to_pixel(x2)
   def get_y1(%{y1: y1}), do: to_pixel(y1)
   def get_y2(%{y2: y2}), do: to_pixel(y2)
-  @impl Element
-  def flipy(%__MODULE__{y1: y1, y2: y2} = line, height) do
-    %__MODULE__{line | y1: height - y1, y2: height - y2}
-  end
 
   defp stroke_dasharray(%{linestyle: "_"}), do: nil
 

lib/matplotex/element/polygon.ex

@@ -15,18 +15,6 @@ defmodule Matplotex.Element.Polygon do
     )
   end
 
-  @impl Element
-  def flipy(%__MODULE__{points: point} = label, height) do
-    %__MODULE__{label | points: flip_point(point, height)}
-  end
-
-  defp flip_point(point, height) do
-    Enum.map(point, &flip_coord(&1, height))
-  end
-
-  defp flip_coord({x, y}, height) do
-    {x, height - y}
-  end
 
   defp assemble_point(%{points: point}) do
     for {x, y} <- point do

lib/matplotex/element/rad_legend.ex

@@ -30,11 +30,6 @@ defmodule Matplotex.Element.RadLegend do
     """
   end
 
-  @impl Element
-  def flipy(%__MODULE__{y: y} = legend, height) do
-    %__MODULE__{legend | y: height - y, label: Label.flipy(legend.label, height)}
-  end
-
   def with_label(
         %__MODULE__{
           label: text,

lib/matplotex/element/rect.ex

@@ -50,8 +50,4 @@ defmodule Matplotex.Element.Rect do
   def get_y(%{y: y}), do: to_pixel(y)
   def get_width(%{width: width}), do: to_pixel(width)
   def get_height(%{height: height}), do: to_pixel(height)
-  @impl Element
-  def flipy(%__MODULE__{y: y} = rect, height) do
-    %__MODULE__{rect | y: height - y}
-  end
 end

lib/matplotex/element/slice.ex

@@ -37,8 +37,4 @@ defmodule Matplotex.Element.Slice do
   def get_cx(%{cx: cx}), do: to_pixel(cx)
   def get_cy(%{cy: cy}), do: to_pixel(cy)
   def get_radius(%{radius: radius}), do: to_pixel(radius)
-  @impl Element
-  def flipy(slice, _height) do
-    slice
-  end
 end

lib/matplotex/element/spline.ex

@@ -0,0 +1,40 @@
+defmodule Matplotex.Element.Spline do
+  alias Matplotex.Element
+  use Element
+  @default_stroke_width 2
+  @default_stroke "black"
+
+  @fill "none"
+  defstruct [
+    :type,
+    :moveto,
+    :cubic,
+    :smooths,
+    fill: @fill,
+    stroke: @default_stroke,
+    stroke_width: @default_stroke_width
+  ]
+
+  @impl Element
+  def assemble(element) do
+    """
+     <path d="M #{to_pixel(element.moveto)}
+     C #{points(element.cubic)} #{smooth_beizer(element.smooths)} "
+      fill="#{element.fill}"
+      stroke="#{element.stroke}"
+      stroke-width="#{element.stroke_width}" />
+    """
+  end
+
+  defp points(points) do
+    for point <- points do
+      "#{to_pixel(point)} "
+    end
+  end
+
+  defp smooth_beizer(points) do
+    for point <- points do
+      "S #{points(point)}"
+    end
+  end
+end

lib/matplotex/element/tick.ex

@@ -17,13 +17,4 @@ defmodule Matplotex.Element.Tick do
      #{Element.assemble(tick.label)}
     )
   end
-
-  @impl Element
-  def flipy(%__MODULE__{label: label, tick_line: tick_line} = tick, height) do
-    %__MODULE__{
-      tick
-      | label: Label.flipy(label, height),
-        tick_line: Line.flipy(tick_line, height)
-    }
-  end
 end

lib/matplotex/figure/areal.ex

@@ -80,13 +80,18 @@ defmodule Matplotex.Figure.Areal do
         |> update_tick(tick)
       end
 
-      def add_ticks(%__MODULE__{tick: tick, size: {width, height}= size} = axes, {key, {_min, _max} = lim}) do
-        number_of_ticks = if key == :x do
-          ceil(width)
-        else
-          ceil(height)
-        end
-        {ticks, lim} = Ticker.generate_ticks(lim, number_of_ticks )
+      def add_ticks(
+            %__MODULE__{tick: tick, size: {width, height} = size} = axes,
+            {key, {_min, _max} = lim}
+          ) do
+        number_of_ticks =
+          if key == :x do
+            ceil(width)
+          else
+            ceil(height)
+          end
+
+        {ticks, lim} = Ticker.generate_ticks(lim, number_of_ticks)
 
         tick = Map.put(tick, key, ticks)
 
@@ -122,7 +127,6 @@ defmodule Matplotex.Figure.Areal do
         %{axes | legend: legend}
       end
 
-
       defp update_limit(%TwoD{x: nil} = limit, :x, xlim) do
         %TwoD{limit | x: xlim}
       end

lib/matplotex/figure/areal/histogram.ex

@@ -23,11 +23,20 @@ defmodule Matplotex.Figure.Areal.Histogram do
   )
 
   @impl Areal
-  def create(%Figure{axes: %__MODULE__{} = axes, rc_params: rc_params} = figure, {data, bins}, opts) do
+  def create(
+        %Figure{axes: %__MODULE__{} = axes, rc_params: rc_params} = figure,
+        {data, bins},
+        opts
+      ) do
     {x, y} = bins_and_hists(data, bins)
 
     dataset = Dataset.cast(%Dataset{x: x, y: y}, opts)
-    %Figure{figure | axes: %__MODULE__{axes | data: {x, y}, dataset: [dataset]}, rc_params: %RcParams{rc_params | y_padding: @make_it_zero}}
+
+    %Figure{
+      figure
+      | axes: %__MODULE__{axes | data: {x, y}, dataset: [dataset]},
+        rc_params: %RcParams{rc_params | y_padding: @make_it_zero}
+    }
     |> PlotOptions.set_options_in_figure(opts)
   end
 
@@ -39,18 +48,38 @@ defmodule Matplotex.Figure.Areal.Histogram do
     |> materialize_hist()
   end
 
-  defp materialize_hist(%Figure{axes: %{dataset: data,limit: %TwoD{x: x_lim, y: y_lim}, region_content: %Region{x: x_region_content, y: y_region_content, width: width_region_content, height: height_region_content}, element: element}, rc_params: %RcParams{x_padding: x_padding, white_space: white_space}}) do
+  defp materialize_hist(%Figure{
+         axes: %{
+           dataset: data,
+           limit: %TwoD{x: x_lim, y: y_lim},
+           region_content: %Region{
+             x: x_region_content,
+             y: y_region_content,
+             width: width_region_content,
+             height: height_region_content
+           },
+           element: element
+         },
+         rc_params: %RcParams{x_padding: x_padding, white_space: white_space}
+       }) do
     x_padding_value = width_region_content * x_padding + white_space
     shrinked_width_region_content = width_region_content - x_padding_value * 2
 
     hist_elements =
-     data
-     |>Enum.map(fn dataset ->
-      dataset
-      |> do_transform(x_lim, y_lim, shrinked_width_region_content, height_region_content, {x_region_content + x_padding_value, y_region_content})
-      |> capture(abs(y_region_content), shrinked_width_region_content)
-     end)
-     |>List.flatten()
+      data
+      |> Enum.map(fn dataset ->
+        dataset
+        |> do_transform(
+          x_lim,
+          y_lim,
+          shrinked_width_region_content,
+          height_region_content,
+          {x_region_content + x_padding_value, y_region_content}
+        )
+        |> capture(abs(y_region_content), shrinked_width_region_content)
+      end)
+      |> List.flatten()
+
     %Figure{axes: %{element: element ++ hist_elements}}
   end
 
@@ -95,12 +124,12 @@ defmodule Matplotex.Figure.Areal.Histogram do
 
   defp capture([], captured, _dataset, _bly, _region_width), do: captured
 
-
   defp bin_position(x, pos_factor) when pos_factor < 0 do
     x + pos_factor
   end
 
   defp bin_position(x, _pos_factor), do: x
+
   defp bins_and_hists(data, bins) do
     {data_min, data_max} = Enum.min_max(data)
 
@@ -118,10 +147,16 @@ defmodule Matplotex.Figure.Areal.Histogram do
     {bins_dist, hists}
   end
 
-  defp sanitize(%Figure{axes: %__MODULE__{data: {x, y}}= axes} = figure) do
+  defp sanitize(%Figure{axes: %__MODULE__{data: {x, y}} = axes} = figure) do
     {ymin, ymax} = Enum.min_max(y)
     {xmin, xmax} = Enum.min_max(x)
 
-    %Figure{figure | axes: %__MODULE__{axes | limit: %TwoD{x: {floor(xmin), ceil(xmax)},y: {floor(ymin), ceil(ymax)}}}}
-   end
+    %Figure{
+      figure
+      | axes: %__MODULE__{
+          axes
+          | limit: %TwoD{x: {floor(xmin), ceil(xmax)}, y: {floor(ymin), ceil(ymax)}}
+        }
+    }
+  end
 end