Runs the categorical null model implemented in nullcat() repeatedly,
generating a batch of randomized matrices or, optionally, a batch of
summary statistics computed from those matrices. This is the categorical
analog of quantize_batch().
Arguments
- x
Community matrix (sites × species) or any categorical matrix of integers.
- n_reps
Number of randomizations to generate. Default is
999.- stat
Optional summary function taking a matrix and returning a numeric statistic. If
NULL(default), the function returns the full set of randomized matrices.- n_cores
Number of compute cores to use for parallel processing. Default is
1.- seed
Integer used to seed random number generator, for reproducibility.
- ...
Additional arguments passed to
nullcat()(e.g.method,n_iter,output).
Value
If stat is NULL, returns a 3D array (rows × cols × n_reps).
If stat is not NULL, returns a numeric array of statistic values
(dimensionality depends on stat).
Examples
set.seed(123)
x <- matrix(sample(1:4, 100, replace = TRUE), nrow = 10)
# Generate 99 randomized matrices
nulls <- nullcat_batch(x, n_reps = 99, method = "curvecat", n_iter = 100)
# Or compute a statistic on each
row_sums <- nullcat_batch(x, n_reps = 99, stat = rowSums,
method = "curvecat", n_iter = 100)
# Specify multiple cores for parallel processing
nulls <- nullcat_batch(x, n_reps = 99, n_iter = 100, n_cores = 2)