Measure-CharacterFrequency.ps1
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<#PSScriptInfo
.DESCRIPTION Measures the letter / character frequency in a block of text, ignoring whitespace .VERSION 1.0.0 .GUID 4bea36de-e693-405d-aff7-f0c3f2c47561 .AUTHOR Lee Holmes #> <# .SYNOPSIS Measures the letter / character frequency in a block of text, ignoring whitespace and PowerShell comment blocks. #> [CmdletBinding(DefaultParameterSetName = "ByPath")] param( ## The path of items with content [Parameter(ParameterSetName = "ByPath", Position = 0)] $Path, ## The literal path of items with content [Parameter(ParameterSetName = "ByLiteralPath", Position = 0, ValueFromPipelineByPropertyName)] [Alias("PSPath")] $LiteralPath, ## The actual content to be measured [Parameter(ParameterSetName = "ByContent")] [String] $Content ) begin { $characterMap = @{} } process { if($PSCmdlet.ParameterSetName -ne "ByContent") { ## If the items were piped in or supplied by Path / LiteralPath, get the content of each of them. Get-ChildItem @PSBoundParameters | Foreach-Object { $content = Get-Content -LiteralPath $_.FullName -Raw ## Remove comments and whitespace ($content -replace '(?s)<#.*?#>','' -replace '#.*','' -replace '(?s)\s','').ToCharArray() | % { $key = $_.ToString().ToUpper() ## And store the character frequency for each character $characterMap[$key] = 1 + $characterMap[$key] } } } else { ## Remove comments and whitespace ($content -replace '(?s)<#.*?#>','' -replace '#.*','' -replace '\s','').ToCharArray() | % { $key = $_.ToString().ToUpper() ## And store the character frequency for each character $characterMap[$key] = 1 + $characterMap[$key] } } } end { ## Figure out how many characters were present in total so that we can calculate a percentage $total = $characterMap.GetEnumerator() | Measure-Object -sum Value | % Sum ## And generate nice object-based output for each character and its frequency $characterMap.GetEnumerator() | Sort-Object -desc value | % { [PSCustomObject] @{ Name = $_.Name; Percent = [Math]::Round($_.Value / $total * 100, 3) } } } |