image.pemt {spMC} | R Documentation |
Images with Multi-directional Transiograms
Description
The function plots -D sections of a multidirectional transiogram computed without any ellipsoidal interpolation.
Usage
## S3 method for class 'pemt'
image(x, main, mar, ask = TRUE, ...,
nlevels = 10, contour = TRUE)
Arguments
x |
an object of class |
main |
the main title (on top) whose font and size are fixed. |
mar |
a scalar or a numerical vector of the form |
ask |
a logical value; if |
... |
other arguments to pass to the function |
nlevels |
the number of levels to pass to the function |
contour |
logical. If |
Details
A multidimensional transiogram is a diagram which shows the transition probabilities for a single pair of categories. The probability is computed for any lag vector through
where entries of are not ellipsoidally interpolated, but they are estimated for the direction specified by the vector
.
The exponential matrix is evaluated by the scaling and squaring algorithm.
Value
An image is produced on the current graphics device. No values are returned.
Author(s)
Luca Sartore drwolf85@gmail.com
References
Carle, S. F., Fogg, G. E. (1997) Modelling Spatial Variability with One and Multidimensional Continuous-Lag Markov Chains. Mathematical Geology, 29(7), 891-918.
Higham, N. J. (2008) Functions of Matrices: Theory and Computation. Society for Industrial and Applied Mathematics.
Sartore, L. (2010) Geostatistical models for 3-D data. M.Phil. thesis, Ca' Foscari University of Venice.
See Also
image.multi_tpfit
, image
, plot.transiogram
Examples
data(ACM)
# Compute a 2-D section of a
# multi-directional transiogram
psEmpTr <- pemt(ACM$MAT3, ACM[, 1:3], 2,
max.dist = c(200, 200, 20),
which.dire=c(1, 3),
mle = "mlk")
# Plot 2-D sections of
# a multi-directional transiogram
image(psEmpTr, col = rev(heat.colors(500)),
breaks = 0:500 / 500, mar = .7,
contour = FALSE)