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+---
+id:
+aliases: []
+title: "2025-12-19"
+tags:
+  - authorship/original
+  - destiny/permanent
+  - status/draft
+  - type/daily
+---
+# 2025-12-19
+
+## 2025-12-19 06:22
+
+PowerShell module to assist in translating between banjo fingerings and concert notes,
+as well as between [[lilypond]] and conventional notation.
+
+```powershell
+$Db4 = [Note]::FromLilyPond("des'")
+$Db4.PlayInTime(1/4,120)
+
+$str1 = [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("d,,,"))
+$str1c2 = $str1.Capo(2)
+
+$openGtuning = [FrettedStringInstrumentTuning]::FromStringTunings(@(
+    [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("d,,,")),
+    [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("b,,")),
+    [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("g,")),
+    [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("d")),
+    [FrettedStringTuning]::FromOpen([Note]::FromLilyPond("g'")),
+    # note: the notation used above is concert octave,
+    # banjo is transposed up one octave.
+))
+$openGtuning.GetNoteFromFingering(4,11).PlayInTime(1/4,120) # play Db4
+
+$openGc2tuning = $openGtuning.Capo(2)
+$openGc2tuning.GetNoteFromFingering(4,9).PlayInTime(1/4,120) # play Db4
+
+# TODO: class FrettedStringInstrument
+
+```
+
+```powershell
+class Note {
+    [Note] TransposeOctave([Note]$note1,[Note]$note2) {}
+    [Note] TransposeOctave([int]$modifier) {}
+}
+```
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