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Extract Images/Volumes for Multiple Coefficients

Source: R/fmri_lm_methods.R, R/fmri_meta_methods.R
coef_images.Rd

A plural companion to coef_image. Returns a named list of volumes (or numeric vectors for non-spatial datasets), one per coefficient, so callers can iterate over or write out every coefficient without reimplementing the loop over coef_names.

Usage

# S3 method for class 'fmri_lm'
coef_images(
  object,
  statistic = c("estimate", "se", "tstat", "prob"),
  type = c("estimates", "contrasts", "F"),
  coefs = NULL,
  ...
)

coef_images(object, ...)

Arguments

object

A fitted model object.

statistic

For fmri_lm objects: one of "estimate", "se", "tstat", or "prob".

type

For fmri_lm objects: which coefficient set to extract: "estimates" (default), "contrasts", or "F".

coefs

Optional character vector of coefficient names (a subset of coef_names(object, type = type)) to extract. Defaults to all coefficients of the requested type.

...

Additional arguments passed to methods (and on to coef_image).

Value

A named list of NeuroVol objects (or numeric vectors when the dataset is non-spatial), named by coefficient.

See also

coef_image, coef_names

Examples

# Create a small example
X <- matrix(rnorm(50 * 4), 50, 4)
edata <- data.frame(
  condition = factor(c("A", "B", "A", "B")),
  onsets = c(1, 12, 25, 38),
  run = c(1, 1, 1, 1)
)
dset <- fmridataset::matrix_dataset(X, TR = 2, run_length = 50,
                                    event_table = edata)
fit <- fmri_lm(onsets ~ hrf(condition), block = ~run, dataset = dset)
# Named list of one volume per event regressor
imgs <- coef_images(fit, statistic = "estimate", type = "estimates")
names(imgs)
#> [1] "condition_condition.A" "condition_condition.B"