Create ggplot2 visualizations of spectral/chromatographic data stored in measure objects.
Arguments
- object
A
measure_tbl,measure_list, orrecipeobject.- ...
Additional arguments passed to specific plot types.
- summary
Logical. If TRUE, add mean +/- SD ribbon. Default FALSE.
- max_spectra
Maximum number of individual spectra to plot. Default 50. Set to NULL for no limit.
- alpha
Transparency for individual spectrum lines. Default 0.3.
- n_samples
Number of samples to show in before/after comparison. Default 10.
- which
Which comparison to show:
"before_after"(default) shows side-by-side before/after comparison,"summary"shows summary statistics (mean +/- SD) for the processed data.
Details
For measure_tbl (single spectrum):
Plots location vs value as a line
For measure_list (multiple spectra):
Plots all spectra with optional summary ribbon
Use
summary = TRUEfor mean +/- SD ribbonUse
max_spectrato limit number of individual lines
For recipe:
Shows before/after comparison of preprocessing
Requires a prepped recipe
Use
n_samplesto control number of samples shown
Examples
if (FALSE) { # \dontrun{
library(ggplot2)
# Single spectrum
spec <- new_measure_tbl(location = 1:100, value = sin(1:100 / 10) + rnorm(100, sd = 0.1))
autoplot(spec)
# Multiple spectra with summary
rec <- recipe(water ~ ., data = meats_long) |>
step_measure_input_long(transmittance, location = vars(channel)) |>
prep()
baked <- bake(rec, new_data = NULL)
autoplot(baked$.measures, summary = TRUE)
# Recipe before/after comparison
rec <- recipe(water ~ ., data = meats_long) |>
update_role(id, new_role = "id") |>
step_measure_input_long(transmittance, location = vars(channel)) |>
step_measure_snv() |>
prep()
autoplot(rec, n_samples = 10)
} # }