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98 lines
3.1 KiB
Markdown
98 lines
3.1 KiB
Markdown
*measure-SelectionSort.ps1*
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================
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This PowerShell script measures the speed of the SelectionSort algorithm.
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SelectionSort is an in-place comparison sorting algorithm. It has an O(n2) time complexity,
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which makes it inefficient on large lists, and generally performs worse than the similar
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insertion sort. Selection sort is noted for its simplicity and has performance advantages
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over more complicated algorithms in certain situations, particularly where auxiliary memory
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is limited.
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Parameters
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----------
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```powershell
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PS> ./measure-SelectionSort.ps1 [[-numIntegers] <Int32>] [<CommonParameters>]
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-numIntegers <Int32>
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Specifies the number of integers to sort
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Required? false
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Position? 1
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Default value 1000
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Accept pipeline input? false
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Accept wildcard characters? false
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[<CommonParameters>]
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This script supports the common parameters: Verbose, Debug, ErrorAction, ErrorVariable, WarningAction,
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WarningVariable, OutBuffer, PipelineVariable, and OutVariable.
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```
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Example
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-------
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```powershell
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PS> ./measure-SelectionSort.ps1
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🧭 0.335 sec to sort 1000 integers by SelectionSort
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```
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Notes
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-----
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Author: Markus Fleschutz | License: CC0
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Related Links
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-------------
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https://github.com/fleschutz/PowerShell
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Script Content
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--------------
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```powershell
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<#
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.SYNOPSIS
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Measures the speed of SelectionSort
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.DESCRIPTION
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This PowerShell script measures the speed of the SelectionSort algorithm.
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SelectionSort is an in-place comparison sorting algorithm. It has an O(n2) time complexity,
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which makes it inefficient on large lists, and generally performs worse than the similar
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insertion sort. Selection sort is noted for its simplicity and has performance advantages
|
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over more complicated algorithms in certain situations, particularly where auxiliary memory
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is limited.
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.PARAMETER numIntegers
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Specifies the number of integers to sort
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.EXAMPLE
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PS> ./measure-SelectionSort.ps1
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🧭 0.335 sec to sort 1000 integers by SelectionSort
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.LINK
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https://github.com/fleschutz/PowerShell
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.NOTES
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Author: Markus Fleschutz | License: CC0
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#>
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param([int]$numIntegers = 1000)
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class SelectionSort {
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static Sort($targetList) {
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$n = $targetList.count
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for ($i = 0; $i -lt $n; $i++) {
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for ($j = $i + 1; $j -lt $n; $j++) {
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if ($targetList[$j] -lt $targetList[$i]) {
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$tmp = $targetList[$i]
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$targetList[$i] = $targetList[$j]
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$targetList[$j] = $tmp
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}
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}
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}
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}
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}
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$list = (1..$numIntegers | foreach{Get-Random -minimum 1 -maximum $numIntegers})
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$stopWatch = [system.diagnostics.stopwatch]::startNew()
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[SelectionSort]::Sort($list)
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[float]$elapsed = $stopWatch.Elapsed.TotalSeconds
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$elapsed3 = "{0:N3}" -f $elapsed # formatted to 3 decimal places
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"🧭 $elapsed3 sec to sort $numIntegers integers by SelectionSort"
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exit 0 # success
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```
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*(generated by convert-ps2md.ps1 using the comment-based help of measure-SelectionSort.ps1 as of 09/20/2023 17:04:42)*
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