separate keys for outlier boudns

Author: PragTob

lib/statistex.ex

@@ -27,7 +27,8 @@ defmodule Statistex do
     :mode,
     :minimum,
     :maximum,
-    :outlier_bounds,
+    :lower_outlier_bound,
+    :upper_outlier_bound,
     :outliers,
     sample_size: 0
   ]
@@ -49,7 +50,8 @@ defmodule Statistex do
           mode: mode,
           minimum: number,
           maximum: number,
-          outlier_bounds: {number, number},
+          lower_outlier_bound: number,
+          upper_outlier_bound: number,
           outliers: [number],
           sample_size: non_neg_integer
         }
@@ -130,7 +132,8 @@ defmodule Statistex do
         sample_size:              9,
         total:                    4500,
         outliers: [],
-        outlier_bounds: {100.0, 900.0}
+        lower_outlier_bound: 100.0,
+        upper_outlier_bound: 900.0
       }
 
       iex> Statistex.statistics([])
@@ -151,7 +154,8 @@ defmodule Statistex do
         sample_size:              4,
         total:                    0,
         outliers: [],
-        outlier_bounds: {0.0, 0.0}
+        lower_outlier_bound: 0.0,
+        upper_outlier_bound: 0.0,
       }
 
   """
@@ -215,6 +219,8 @@ defmodule Statistex do
     standard_deviation_ratio =
       standard_deviation_ratio(samples, standard_deviation: standard_deviation)
 
+    {lower_outlier_bound, upper_outlier_bound} = outlier_bounds
+
     %__MODULE__{
       total: total,
       average: average,
@@ -227,7 +233,8 @@ defmodule Statistex do
       mode: mode(samples, frequency_distribution: frequency_distribution),
       minimum: minimum,
       maximum: maximum,
-      outlier_bounds: outlier_bounds,
+      lower_outlier_bound: lower_outlier_bound,
+      upper_outlier_bound: upper_outlier_bound,
       outliers: outliers,
       sample_size: sample_size
     }

test/statistex_test.exs

@@ -40,7 +40,8 @@ defmodule Statistex.StatistexTest do
                  mode: [500, 400],
                  minimum: 200,
                  maximum: 900,
-                 outlier_bounds: {100.0, 900.0},
+                 lower_outlier_bound: 100.0,
+                 upper_outlier_bound: 900.0,
                  outliers: [],
                  sample_size: 9
                }
@@ -60,7 +61,8 @@ defmodule Statistex.StatistexTest do
                  mode: [500, 450],
                  minimum: 50,
                  maximum: 900,
-                 outlier_bounds: {87.5, 787.5},
+                 lower_outlier_bound: 87.5,
+                 upper_outlier_bound: 787.5,
                  outliers: [50, 50, 900],
                  sample_size: 10
                }
@@ -85,7 +87,8 @@ defmodule Statistex.StatistexTest do
                percentiles: %{25 => 9.25, 50 => 10.0, 75 => 11.75},
                minimum: 9,
                maximum: 36,
-               outlier_bounds: {5.5, 15.5},
+               lower_outlier_bound: 5.5,
+               upper_outlier_bound: 15.5,
                outliers: [36]
              } = Statistex.statistics([9, 9, 10, 10, 10, 11, 12, 36], exclude_outliers: false)
     end
@@ -123,7 +126,8 @@ defmodule Statistex.StatistexTest do
                median: 70.0,
                percentiles: %{25 => 66.0, 50 => 70.0, 75 => 75.0},
                # report interquantile range?
-               outlier_bounds: {52.5, 88.5},
+               lower_outlier_bound: 52.5,
+               upper_outlier_bound: 88.5,
                outliers: [52, 89]
              } = Statistex.statistics(data, exclude_outliers: false)
     end