Hashtable measurements

group-object-example.ps1

<#
some testing results:
machine1
.\group-object-example.ps1
PS 7.3.4
Foreach: 0.0210048
Group: 0.1844798

.\group-object-example.ps1
PS 5.1.22621.1778
Foreach : 0.0373328
Group   : 62.6519559

machine2
.\group-object-example.ps1
PS 5.1.14393.5582
Foreach : 0.5106424
Group   : 111.8423285

.\group-object-example.ps1
PS 7.3.4
Foreach : 0.0606677
Group   : 0.5708983
#>

$test = 1..30000 | ForEach-Object {
    Get-Random
}
$hash = Measure-Command -Expression {
    $hashtable = @{}
    foreach ($item in $test) {
        $hashtable[$item] = $item
    }
}
$group = Measure-Command -Expression {
    $grouphash = $test | Group-Object -AsHashTable
}
Write-Output "PS $($PSVersionTable.PSVersion.ToString()) `nForeach`t: $($hash.TotalSeconds) `nGroup`t: $($group.totalseconds)"