The plot_fretboard function can be used to create general fretboard diagrams directly in R using ggplot and plot_chord specifically produces single chord diagrams, but this vignette shows how to create a standalone chord chart using LilyPond. Instead of using tab to render a score to pdf that may contain a chord chart at the top of the first page, you can use render_chordchart. This function creates the necessary LilyPond file and sends it to LilyPond for final rendering.

## Prepare chords

For consistency, render_chordchart takes chord input in the same way that the score function does, as a named character vector. The chords and their names are in the same format.

Filter the guitarChords dataset down to chords:

• whose root note is either C or F
• the chords is either a 7th, major 7th, or minor 7th
• the chords do not contain sharps
• and the fret number of the root note is no higher than 12
library(dplyr)

chords <- filter(
guitarChords,
root %in% c("c", "f") &
id %in% c("7", "M7", "m7") &
!grepl("#", notes) & root_fret <= 12
) %>%
arrange(root, id)

chords <- setNames(chords$fretboard, chords$lp_name)
#>              c:7              c:7              c:7              c:7
#>   "x;3;2;3;1;x;"   "x;3;5;3;5;3;"   "x;3;2;3;1;3;"  "8;10;8;9;8;8;"
#>              c:7             c':7
#>   "8;x;8;9;8;x;" "x;x;10;9;11;8;"

## Render chord chart

The filtering above results in 41 chords. The size of the fretboard diagrams is increased below with size = 2. Like lilypond and the render_* functions that wrap around it for rendering music scores, render_chordchart also takes the header and paper named list arguments. Once the named chord vector is ready, rendering the chord chart is as simple as the following.

hdr <- list(
title = "Dominant 7th, major 7th and minor 7th chords",
subtitle = "C and F root"
)
render_chordchart(chords, "out.png", 2, hdr, list(textheight = 175))

The chord chart template must be kept to one page.