readyomics (version 0.1.1)

permanova: PERMANOVA with flexible permutation control

Description

Performs PERMANOVA (Permutational Multivariate Analysis of Variance). Supports both joint-term (default vegan::adonis2()) and single-term testing when independent = TRUE. Several distance methods, and fine-grained permutation control.

Usage

permanova(
  X,
  sample_data,
  formula_rhs,
  dist_control = list(method = "euclidean", diag = FALSE, upper = FALSE),
  perm_control = list(joint_terms = list(control = permute::how(blocks = NULL, nperm =
    999))),
  independent = TRUE,
  platform = c("ms", "nmr", "ngs"),
  assay = NULL,
  seed = NULL,
  verbose = TRUE,
  ...
)

Value

A named list with three elements:

X_dist

A dist object.

perm_matrix_joint

A matrix from permute::shuffleSet() joint_terms control.

permanova_joint

A data.frame of PERMANOVA results using the full model.

permanova_indep

A data.frame of a PERMANOVA results for each predictor, or NULL if independent = FALSE.

Arguments

X

A processed matrix or data frame of features (samples in rows, features in columns).

sample_data

A data.frame containing sample-level data. Row names must match those in X.

formula_rhs

A one-sided formula (e.g., ~ group + age).

dist_control

A named list of arguments to control distance calculation. Must contain at least method. Defaults to "Euclidean" via stats::dist().

perm_control

A named list specifying permute::shuffleSet() parameters. By default, joint_terms parameters will be used, with same vegan::adonis2() defaults, unless variable-specific permutation settings are added as named list elements (e.g. perm_control = list(joint_terms = , age = , sex = )).

independent

Logical. If TRUE, a PERMANOVA test for each variable in formula_rhs is performed.

platform

A string specifying the omics platform ("ms", "nmr", "ngs"). Used for annotation.

assay

Optional. Character string giving the assay name for annotation (e.g., "lipidomics").

seed

Optional integer. If provided, sets the random seed for reproducible permutation results.

verbose

Logical. If TRUE, prints diagnostic messages.

...

Additional arguments passed to vegan::adonis2().

Details

• Supports both stats::dist() and vegan::vegdist() for distance matrix computation.

• Distance method must be specified in dist_control$method.

• Permutation design is controlled via the permute package using permute::shuffleSet().

• If seed is supplied, the same permutations will be used across runs for reproducibility.

See Also

• stats::dist() and vegan::vegdist() for information on available distances.

• vegan::adonis2() and permute::shuffleSet() for control options and details.

• process_ngs() to pre-process and normalize an X NGS dataset.

• process_ms() to pre-process and normalize an X MS dataset.

Examples

# Mock data
X <- matrix(rnorm(40), nrow = 10,
            dimnames = list(paste0("sample", 1:10),
                            paste0("feat", 1:4)))
sample_data <- data.frame(
  sample_id = rownames(X),
  group = factor(rep(c("A", "B"), each = 5)),
  age = rep(20:29, length.out = 10),
  row.names = rownames(X),
  stringsAsFactors = FALSE
)

# Simple control structures
dist_control <- list(method = "euclidean")
perm_control <- list(
  joint_terms = list(control = permute::how(blocks = NULL, nperm = 9)),
  group = list(control = permute::how(blocks = NULL, nperm = 9)),
  age = list(control = permute::how(blocks = NULL, nperm = 9))
)

result <- permanova(
  X = X,
  sample_data = sample_data,
  formula_rhs = ~ group + age,
  dist_control = dist_control,
  perm_control = perm_control,
  independent = TRUE,
  platform = "ms",
  assay = "lipidomics",
  seed = 42,
  verbose = FALSE
)