Get track label as expression for plotting — get_track_label

Extended version of get_track_label() that returns plotmath expressions with subscripts when use_subscripts = TRUE.

Usage

get_track_label_expr(df, col, full = FALSE, use_subscripts = TRUE)

Arguments

df: data.frame or tibble. Data frame from as.data.frame.AsspDataObj().
col: Character. Column name.
full: Logical. If TRUE, return full descriptive label. Default: FALSE.
use_subscripts: Logical. If TRUE, return plotmath expression with subscripts. If FALSE, return plain text. Default: TRUE.

Value

Expression object (if use_subscripts = TRUE) or character string.

Details

This function extends get_track_label() with the option to generate plotmath expressions for scientific subscripts in ggplot2.

With subscripts (use_subscripts = TRUE):

fo → f[o] (f subscript o)
F1 → F[1] (F subscript 1)
H1-H2c → H[1]-H[2c] (proper subscripts)

Without subscripts (use_subscripts = FALSE):

Same as get_track_label()
Returns: "fo [Hz]", "F1 [Hz]", "H1-H2c [dB]"

For full descriptive labels (full = TRUE), subscripts are not used as the full text doesn't need them (e.g., "Frequency of oscillation [Hz]").

Examples

if (FALSE) { # \dontrun{
fms <- wrassp::forest("audio.wav", toFile = FALSE)
df <- as.data.frame(fms)

# Get expression with subscript
expr <- get_track_label_expr(df, "F1_Hz")
# Returns: expression(F\[1\]~"\[Hz\]")

# Use in ggplot
library(ggplot2)
ggplot(df, aes(x = frame_time, y = F1_Hz)) +
  geom_line() +
  labs(y = get_track_label_expr(df, "F1_Hz"))
# Y-axis shows: F₁ \[Hz\] (with subscript)

# Without subscripts
label <- get_track_label_expr(df, "F1_Hz", use_subscripts = FALSE)
# Returns: "F1 \[Hz\]"
} # }