NormalScore and BackTransform: GSLIB normal-score transform
and its linear back-transform. SgsSimulate: sequential Gaussian
simulation with simple or ordinary kriging on a Philox random path, and
collocated co-simulation under Markov model 1. SisSimulate:
sequential indicator simulation (continuous thresholds with order-relation
correction, or categories). SimulationSummary: E-type, variance,
percentile and exceedance maps, histogram reproduction and block
averages. SgsCrossValidation: leave-one-out validation.
TransitionMatrix and MarkovChainSimulate: transition
probabilities and categorical Markov-chain simulation. Identical to the
Python arm morie.fn.seqsim (paths and classes are 1-based here).
Usage
NormalScore(z)
BackTransform(y, table_z, table_y)
SgsSimulate(
coords,
z,
grid,
model,
kriging = "simple",
mean = 0,
nmax = 16,
nsim = 1,
seed = 1,
secondary = NULL,
rho = 0
)
SisSimulate(
coords,
z,
grid,
thresholds,
models,
nmax = 16,
nsim = 1,
seed = 1,
categorical = FALSE,
proportions = NULL
)
SimulationSummary(
realizations,
probs = c(0.1, 0.5, 0.9),
threshold = NULL,
data = NULL,
blocks = NULL
)
SgsCrossValidation(
coords,
z,
model,
kriging = "simple",
mean = 0,
nmax = 16,
nsim = 100,
seed = 1,
level = 0.9
)
TransitionMatrix(sequences, categories = NULL)
MarkovChainSimulate(T, start, n, seed = 1, conditioning = NULL)Arguments
- z
Data values (normal scores for
SgsSimulate).- y
Normal scores to back-transform.
- table_z, table_y
Transformation table.
- coords
Two-column data coordinates.
- grid
Two-column simulation nodes.
- model
Covariance model (see
KrigingCovariance).- kriging
"simple"or"ordinary".- mean
Simple kriging mean.
- nmax
Maximum conditioning values.
- nsim
Number of realisations.
- seed
Philox seed.
- secondary
Standardised secondary value at each grid node.
- rho
Primary-secondary correlation.
- thresholds
Thresholds or category codes.
- models
Indicator covariance model(s).
- categorical
Categorical variable.
- proportions
Prior proportions.
- realizations
Matrix of realisations (rows).
- probs
Percentile probabilities.
- threshold
Exceedance threshold.
- data
Data for histogram reproduction.
- blocks
Block id per node.
- level
Interval level.
- sequences
List of categorical sequences.
- categories
Category order.
- T
Transition matrix.
- start
Initial category (0-based).
- n
Sequence length.
- conditioning
Named list mapping 0-based positions to categories.
References
Deutsch, C. V. and Journel, A. G. (1998). GSLIB: Geostatistical Software Library and User's Guide, 2nd ed. Oxford University Press.
Almeida, A. S. and Journel, A. G. (1994). Joint simulation of multiple variables with a Markov-type coregionalization model. Mathematical Geology 26, 565-588.
Carle, S. F. and Fogg, G. E. (1996). Transition probability-based indicator geostatistics. Mathematical Geology 28, 453-476.