How to resolve the algorithm Averages/Median step by step in the PowerShell programming language

Published on 12 May 2024 09:40 PM
#Powershell

How to resolve the algorithm Averages/Median step by step in the PowerShell programming language

Table of Contents

Problem Statement

Write a program to find the   median   value of a vector of floating-point numbers. The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements.   In that case, return the average of the two middle values. There are several approaches to this.   One is to sort the elements, and then pick the element(s) in the middle. Sorting would take at least   O(n logn).   Another approach would be to build a priority queue from the elements, and then extract half of the elements to get to the middle element(s).   This would also take   O(n logn).   The best solution is to use the   selection algorithm   to find the median in   O(n)   time. Quickselect_algorithm

Let's start with the solution:

Step by Step solution about How to resolve the algorithm Averages/Median step by step in the PowerShell programming language

Source code in the powershell programming language

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
    }
}


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


$statistics.Median

You may also check:How to resolve the algorithm Entropy step by step in the Euler Math Toolbox programming language
You may also check:How to resolve the algorithm Animation step by step in the Logo programming language
You may also check:How to resolve the algorithm Abundant, deficient and perfect number classifications step by step in the TypeScript programming language
You may also check:How to resolve the algorithm Sorting algorithms/Merge sort step by step in the Sidef programming language
You may also check:How to resolve the algorithm Scope/Function names and labels step by step in the Tcl programming language