Polynomial from Wikipedia

Author: devstopfix

examples/polynomial.exs

@@ -0,0 +1,47 @@
+defmodule Polynomial do
+  @moduledoc """
+  Polynomials graphs from Wikipedia.
+
+  https://en.wikipedia.org/wiki/Polynomial#Graphs
+  """
+
+  def png, do: Path.join("/tmp/", "polynomial.PNG")
+
+  def target,
+    do: [
+      [:set, :term, :pngcairo, :size, '400,400', :font, "Times,14"],
+      [:set, :output, png()]
+    ]
+
+  def style,
+    do: [
+      ~w(set style line 1 lw 3 lc '#DD0000')a,
+      ~w(set style line 2 lw 3 lc '#000000')a,
+      ~w(set style line 3 lw 1 lc '#CECECE')a,
+      ~w(set xzeroaxis ls 2)a,
+      ~w(set yzeroaxis ls 2)a,
+      ~w(set grid ls 3)a,
+      [:set, :xrange, -5..4],
+      [:set, :yrange, -4..6],
+      [:set, :format, :x, ""],
+      [:set, :format, :y, ""],
+      ~w(set border ls 3)a
+    ]
+
+  def commands,
+    do: [
+      [:set, :title, "Wikipedia Polynomial"],
+      [
+        :plot,
+        '((x**3)/4)+(3*(x**2)/4)-(3*x/2)-2',
+        :ls,
+        1,
+        :notitle
+      ]
+    ]
+
+  def plot, do: {:ok, _} = Gnuplot.plot(target() ++ style() ++ commands())
+end
+
+# mix run examples/polynomial.exs
+Polynomial.plot()