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Plot a dated tree-ring series with a reference series or chronology

Source: R/trs_plot_dated.R
trs_plot_dated.Rd

Creates a line plot of a dated tree-ring series and a reference chronology, with optional z-score standardization, statistical annotations, and visual highlighting of synchronous growth changes (SCG).

Usage

trs_plot_dated(
  x,
  y,
  end_year = NULL,
  zscore = TRUE,
  pv_highlight = TRUE,
  pv_alpha = 0.2,
  show_stats = TRUE,
  labels = TRUE,
  label_size = 3
)

Arguments

x

A data.frame (typically of class 'rwl') with one column of ring-width values. Row names must be numeric and represent calendar years.

y

A data.frame (typically of class 'rwl') with one column of ring-width values. Row names must be numeric and represent calendar years.

end_year

Optional numeric. If provided, the rownames of x will be set to match this year for the last ring (using trs_end_date()).

zscore

Logical. If TRUE, the ring-width series are standardized to z-scores before plotting. Defaults to TRUE.

pv_highlight

Logical. If TRUE, highlights regions of parallel variation (synchronous growth change - sgc) using shaded bars. Defaults to TRUE.

pv_alpha

Numeric between 0 and 1. Controls the transparency of the parallel variation highlight. Defaults to 0.2.

show_stats

Logical. If TRUE, displays crossdating statistics (e.g., overlap, correlation, sgc, t-values) as a plot subtitle. Defaults to TRUE.

labels

Logical. If TRUE, displays year labels and points at the start and end positions. If FALSE, neither labels nor points are shown. Defaults to TRUE.

label_size

Numeric. Controls the size of the year labels. Defaults to 3.

Value

A ggplot object showing the plotted time series.

Details

The function assumes that x and y are already calendar-dated and aligned by row names. It performs internal trimming and optional z-scoring before plotting. Crossdating statistics are computed using trs_crossdate(), and regions of synchronous growth change (SGC) are highlighted. Required helper functions include: trs_trim, trs_zscore, trs_end_date, and sgc_for_plot. Statistics are derived from trs_crossdate.

Required packages: ggplot2, ggtext, plyr

Examples

x <- trs_pseudo_rwl(n_series = 1, series_length = 80, end_date = 1500, prefix = "trs_")
y <- trs_pseudo_rwl(n_series = 1, series_length = 400, end_date = 1700, prefix = "ref_")
trs_plot_dated(x, y)
#> Warning: Ignoring unknown parameters: `linewidth`