Data commit

Task/Averages-Median/PowerShell/averages-median-1.psh

@@ -0,0 +1,69 @@
+function Measure-Data
+{
+    [CmdletBinding()]
+    [OutputType([PSCustomObject])]
+    Param
+    (
+        [Parameter(Mandatory=$true,
+                   Position=0)]
+        [double[]]
+        $Data
+    )
+
+    Begin
+    {
+        function Get-Mode ([double[]]$Data)
+        {
+            if ($Data.Count -gt ($Data | Select-Object -Unique).Count)
+            {
+                $groups = $Data | Group-Object | Sort-Object -Property Count -Descending
+
+                return ($groups | Where-Object {[double]$_.Count -eq [double]$groups[0].Count}).Name | ForEach-Object {[double]$_}
+            }
+            else
+            {
+                return $null
+            }
+        }
+
+        function Get-StandardDeviation ([double[]]$Data)
+        {
+            $variance = 0
+            $average  = $Data | Measure-Object -Average | Select-Object -Property Count, Average
+
+            foreach ($number in $Data)
+            {
+                $variance +=  [Math]::Pow(($number - $average.Average),2)
+            }
+
+            return [Math]::Sqrt($variance / ($average.Count-1))
+        }
+
+        function Get-Median ([double[]]$Data)
+        {
+            if ($Data.Count % 2)
+            {
+                return $Data[[Math]::Floor($Data.Count/2)]
+            }
+            else
+            {
+                return ($Data[$Data.Count/2], $Data[$Data.Count/2-1] | Measure-Object -Average).Average
+            }
+        }
+    }
+    Process
+    {
+        $Data = $Data | Sort-Object
+
+        $Data | Measure-Object -Maximum -Minimum -Sum -Average |
+                Select-Object -Property Count,
+                                        Sum,
+                                        Minimum,
+                                        Maximum,
+                                        @{Name='Range'; Expression={$_.Maximum - $_.Minimum}},
+                                        @{Name='Mean' ; Expression={$_.Average}} |
+                Add-Member -MemberType NoteProperty -Name Median            -Value (Get-Median $Data)            -PassThru |
+                Add-Member -MemberType NoteProperty -Name StandardDeviation -Value (Get-StandardDeviation $Data) -PassThru |
+                Add-Member -MemberType NoteProperty -Name Mode              -Value (Get-Mode $Data)              -PassThru
+    }
+}

Task/Averages-Median/PowerShell/averages-median-2.psh

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+$statistics = Measure-Data 4, 5, 6, 7, 7, 7, 8, 1, 1, 1, 2, 3
+$statistics

Task/Averages-Median/PowerShell/averages-median-3.psh

@@ -0,0 +1 @@
+$statistics.Median