Extract Sample from Dataset — data

Extract a sample from a given dataset object.

Construct a light-weight data sample descriptor for a set of features (e.g., voxels) associated with a dataset. Methods define how to interpret and convert this descriptor.

Usage

data_sample(obj, vox, ...)

# S3 method for class 'mvpa_dataset'
data_sample(obj, vox, ...)

# S3 method for class 'mvpa_multibasis_image_dataset'
data_sample(obj, vox, ...)

Arguments

obj: An object (typically a dataset) from which to draw a sample.
vox: The feature indices or coordinates defining the sample.
...: Additional arguments passed to methods.

Value

A sample extracted from the dataset.

An object of class `data_sample` describing the sample; methods provide conversions to ROI structures or data frames as needed.

Examples

if (FALSE) { # \dontrun{
  ds <- gen_sample_dataset(c(5,5,5), 20)
  vox <- sample(which(ds$dataset$mask > 0), 10)
  samp <- data_sample(ds$dataset, vox)
} # }