LetterToFrequency

LetterToFrequency

Converts Letter Notes to Frequencies

Converts one or more letter notes into a series of corresponding frequencies.

wave LetterToFrequency "c3", "c#3", 
    "d3", "d#3", 
    "e3", "f3", 
    "f#3", "g3", 
    "g#3", "a3", 
    "a#3","b3"

Parameters

LetterNote

required	type	position	pipeline	wildcard	aliases
false	String[]	1	false	false

View Source

<#
.SYNOPSIS
    Converts Letter Notes to Frequencies
.DESCRIPTION
    Converts one or more letter notes into a series of corresponding frequencies.
.EXAMPLE
    wave LetterToFrequency "c3", "c#3", 
        "d3", "d#3", 
        "e3", "f3", 
        "f#3", "g3", 
        "g#3", "a3", 
        "a#3","b3"
#>
param([string[]]$LetterNote)

$currentWave = $this
if (-not $currentWave) { $currentWave = wave}
$noteFrequency = $currentWave.NoteFrequency
$frequencies = @(foreach ($letter in $LetterNote) {
    if ($noteFrequency[$letter]) {
        $noteFrequency[$letter]
    }
    elseif ($noteFrequency[$letter -replace '#', '♯']) {
        $noteFrequency[$letter -replace '#', '♯']
    } 
    elseif ($noteFrequency[$letter -replace 'b(?<n>\d)', '♭${n}']) {
        $noteFrequency[$letter -replace 'b(?<n>\d)', '♭${n}']
    } 
    elseif (
        $letter -cmatch '^\p{Lu}$' -and 
        $noteFrequency["${letter}4"]
    ) {
        $noteFrequency["${letter}4"]
    } elseif (
        $letter -cmatch '^\p{Ll}$' -and 
        $noteFrequency["${letter}3"]
    ) {
        $noteFrequency["${letter}3"]
    } 
})
foreach ($frequency in $frequencies) {
    $frequency.pstypenames.add('Frequency')
    $frequency
}