Get-Histogram.ps1
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function Get-Histogram { [CmdletBinding(DefaultParameterSetName='BucketCount')] Param( [Parameter(Mandatory, ValueFromPipeline, Position=1)] [ValidateNotNullOrEmpty()] [array] $InputObject , [Parameter(Mandatory, Position=2)] [ValidateNotNullOrEmpty()] [string] $Property , [Parameter()] [ValidateNotNullOrEmpty()] [float] $Minimum , [Parameter()] [ValidateNotNullOrEmpty()] [float] $Maximum , [Parameter()] [ValidateNotNullOrEmpty()] [Alias('Width')] [float] $BucketWidth = 1 , [Parameter()] [ValidateNotNullOrEmpty()] [Alias('Count')] [float] $BucketCount ) Begin { Write-Verbose ('[{0}] Initializing' -f $MyInvocation.MyCommand) $Buckets = @{} $Data = @() } Process { Write-Verbose ('[{0}] Processing {1} items' -f $MyInvocation.MyCommand, $InputObject.Length) $InputObject | ForEach-Object { if (-Not ($_ | Select-Object -ExpandProperty $Property -ErrorAction SilentlyContinue)) { throw ('Input object does not contain a property called <{0}>.' -f $Property) } $Data += $_ } } End { Write-Verbose ('[{0}] Building histogram' -f $MyInvocation.MyCommand) Write-Debug ('[{0}] Retrieving measurements from upstream cmdlet.' -f $MyInvocation.MyCommand) $Stats = $Data | Microsoft.PowerShell.Utility\Measure-Object -Minimum -Maximum -Property $Property if (-Not $PSBoundParameters.ContainsKey('Minimum')) { $Minimum = $Stats.Minimum Write-Debug ('[{0}] Minimum value not specified. Using smallest value ({1}) from input data.' -f $MyInvocation.MyCommand, $Minimum) } if (-Not $PSBoundParameters.ContainsKey('Maximum')) { $Maximum = $Stats.Maximum Write-Debug ('[{0}] Maximum value not specified. Using largest value ({1}) from input data.' -f $MyInvocation.MyCommand, $Maximum) } if (-Not $PSBoundParameters.ContainsKey('BucketCount')) { $BucketCount = [math]::Ceiling(($Maximum - $Minimum) / $BucketWidth) Write-Debug ('[{0}] Bucket count not specified. Calculated {1} buckets from width of {2}.' -f $MyInvocation.MyCommand, $BucketCount, $BucketWidth) } if ($BucketCount -gt 100) { Write-Warning ('[{0}] Generating {1} buckets' -f $MyInvocation.MyCommand, $BucketCount) } Write-Debug ('[{0}] Building buckets using: Minimum=<{1}> Maximum=<{2}> BucketWidth=<{3}> BucketCount=<{4}>' -f $MyInvocation.MyCommand, $Minimum, $Maximum, $BucketWidth, $BucketCount) $OverallCount = 0 $Buckets = 1..$BucketCount | ForEach-Object { [pscustomobject]@{ Index = $_ lowerBound = $Minimum + ($_ - 1) * $BucketWidth upperBound = $Minimum + $_ * $BucketWidth Count = 0 RelativeCount = 0 Group = @() PSTypeName = 'HistogramBucket' } } Write-Debug ('[{0}] Building histogram' -f $MyInvocation.MyCommand) $Data | ForEach-Object { $Value = $_.$Property if ($Value -ge $Minimum -and $Value -le $Maximum) { $BucketIndex = [math]::Floor(($Value - $Minimum) / $BucketWidth) if ($BucketIndex -lt $Buckets.Length) { $Buckets[$BucketIndex].Count += 1 $Buckets[$BucketIndex].Group += $_ $OverallCount += 1 } } } Write-Debug ('[{0}] Adding relative count' -f $MyInvocation.MyCommand) $Buckets | ForEach-Object { $_.RelativeCount = $_.Count / $OverallCount } Write-Debug ('[{0}] Returning histogram' -f $MyInvocation.MyCommand) $Buckets } } New-Alias -Name gh -Value Get-Histogram -Force |