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Compares tree-ring series in two data frames using Gleichläufigkeit (GLK) and Synchronous Growth Changes (SGC), adapted from the dplR package.

Usage

trs_pv(x, y = NULL, min_overlap = 50, prob = TRUE, as_df = FALSE)

Arguments

x

A data frame of test tree-ring series (rwl format: years in rows, series in columns).

y

A data frame of reference series (rwl format).

min_overlap

Integer. Minimum number of overlapping years required for computing GLK/SGC statistics. Default is 50.

prob

Logical. If TRUE (default), computes two-tailed p-values for GLK and SGC.

as_df

Logical. If TRUE, returns a long-format data.frame with all combinations and results. Default is FALSE.

Value

If as_df = FALSE, a list with components:

glk

Matrix of Gleichläufigkeit values.

glk_p

Matrix of GLK p-values (if prob = TRUE).

sgc

Matrix of synchronous growth change values.

ssgc

Matrix of semi-synchronous growth change values.

sgc_p

Matrix of SGC p-values (if prob = TRUE).

overlap

Matrix of the number of overlapping years used in each comparison.

If as_df = TRUE, returns a data frame with columns: series, reference, glk, glk_p, sgc, ssgc, sgc_p, and overlap.

Examples

# Create sample data,
trs <- trs_pseudo_rwl(n_series = 5, series_length = c(80, 100), end_date = c(2010, 2020))
trs_pv(trs)$sgc
#>       trs_1 trs_2 trs_3 trs_4 trs_5
#> trs_1 100.0  81.5  71.0  79.6  78.7
#> trs_2  81.5 100.0  71.0  75.0  75.3
#> trs_3  71.0  71.0 100.0  70.2  75.3
#> trs_4  79.6  75.0  70.2 100.0  79.8
#> trs_5  78.7  75.3  75.3  79.8 100.0