Function transposeChordSymbol

transposeChordSymbol(
    text: string,
    semitones: number,
    opts?: ChordSymbolOptions,
): string
Transpose a chord symbol by a number of semitones.

The symbol is read in the same system it is written back in, so a German chart stays German across the transposition.

The root and the bass are respelled where moving them by letter would leave a name no chart writes, so raising a flat chart a semitone gives Bmaj7 rather than Cbmaj7. Pass flats to write the whole symbol on one side of the staff, root and bass together.
Parameters
- text: string
  The chord symbol text.
- semitones: number
  Signed semitone offset to apply to the root and bass.
- Optionalopts: ChordSymbolOptions
  Options for reading and writing the symbol; see ChordSymbolOptions.
Returns string
The transposed chord symbol text.
Throws
If text does not parse as a chord symbol.
Example
```
import { transposeChordSymbol } from '@libraz/libcantus';
transposeChordSymbol('C/G', 2); // 'D/A'
transposeChordSymbol('H7', 1, { system: 'german' }); // 'C7'
```
- Defined in src/theory/symbol/index.ts:416