chore(growth): add example for Growth.new/4

lib/growth/growth.ex

@@ -87,6 +87,70 @@ defmodule Growth do
   * `:subscapular_skinfold`: subscapular skinfold in milimeters, defaults to `nil`.
   * `:triceps_skinfold`: triceps skinfold in milimeters, defaults to `nil`.
 
+  ## Examples
+
+      iex> Growth.new(
+      ...>   "child a",
+      ...>   :male,
+      ...>   ~D[2024-01-01],
+      ...>   date_of_measurement: ~D[2024-04-01],
+      ...>   weight: 8,
+      ...>   height: 65.4,
+      ...>   arm_circumference: 15.5,
+      ...>   head_circumference: 42.8,
+      ...>   subscapular_skinfold: 10.9,
+      ...>   triceps_skinfold: 13.5
+      ...> )
+      %Growth{
+        name: "child a",
+        gender: :male,
+        date_of_birth: ~D[2024-01-01],
+        date_of_measurement: ~D[2024-04-01],
+        age_in_days: 91,
+        age_in_weeks: 13,
+        age_in_months: 2,
+        weight: 8,
+        height: 65.4,
+        arm_circumference: 15.5,
+        head_circumference: 42.8,
+        subscapular_skinfold: 10.9,
+        triceps_skinfold: 13.5,
+        bmi: 18.703999850368,
+        results: [
+          %{
+            head_circumference: [
+              {"day", {1.945484886994137, 42.800000000000004}},
+              {"week", {1.945484886994137, 42.800000000000004}},
+              {"month", {3.130859582465616, :na}}
+            ]
+          },
+          %{arm_circumference: [{"day", {1.9227031505630465, 15.499999999999996}}]},
+          %{subscapular_skinfold: [{"day", {1.9437372448689536, 10.9}}]},
+          %{triceps_skinfold: [{"day", {1.950277062993091, 13.500000000000353}}]},
+          %{
+            weight: [
+              {"day", {1.982458622036091, 8.0}},
+              {"week", {1.982458622036091, 8.0}},
+              {"month", {3.0355951313091745, :na}}
+            ]
+          },
+          %{
+            height: [
+              {"day", {1.956263992749136, 65.4}},
+              {"week", {1.956263992749136, 65.4}},
+              {"month", {3.4867331002754054, :na}}
+            ]
+          },
+          %{
+            bmi: [
+              {"day", {1.1977344927294398, 18.703999850368085}},
+              {"week", {1.1977344927294398, 18.703999850368085}},
+              {"month", {1.5837461190318038, 18.703999850367996}}
+            ]
+          }
+        ]
+      }
+
   """
   @spec new(String.t(), gender(), Date.t(), opts()) :: t()
   def new(name, gender, date_of_birth, opts \\ []) do