plot_anisotropy {sdmTMB} | R Documentation |
Plot anisotropy from an sdmTMB model
Description
Anisotropy is when spatial correlation is directionally dependent. In
sdmTMB()
, the default spatial correlation is isotropic, but anisotropy can
be enabled with anisotropy = TRUE
. These plotting functions help visualize
that estimated anisotropy.
Usage
plot_anisotropy(object, return_data = FALSE)
plot_anisotropy2(object, model = 1)
Arguments
object |
An object from |
return_data |
Logical. Return a data frame? |
model |
Which model if a delta model (only for |
Value
plot_anisotropy()
: One or more ellipses illustrating the estimated
anisotropy. The ellipses are centered at coordinates of zero in the space of
the X-Y coordinates being modeled. The ellipses show the spatial and/or
spatiotemporal range (distance at which correlation is effectively
independent) in any direction from zero. Uses ggplot2. If anisotropy
was turned off when fitting the model, NULL
is returned instead of a
ggplot2 object.
plot_anisotropy2()
: A plot of eigenvectors illustrating the estimated
anisotropy. A list of the plotted data is invisibly returned. Uses base
graphics. If anisotropy was turned off when fitting the model, NULL
is
returned instead of a plot object.
References
Code adapted from VAST R package
Examples
mesh <- make_mesh(pcod_2011, c("X", "Y"), n_knots = 80, type = "kmeans")
fit <- sdmTMB(
data = pcod_2011,
formula = density ~ 1,
mesh = mesh,
family = tweedie(),
share_range = FALSE,
time = "year",
anisotropy = TRUE #<
)
plot_anisotropy(fit)
plot_anisotropy2(fit)