indexList {tractor.base}

Extract one or more elements from a list

Description

Given a list-like first argument, this function extracts one or more of its elements. Numeric and character indexing are allowed.

Usage

indexList(list, index = NULL)

Arguments

list

A list-like object, with a [[ indexing method.

index

A vector of integers or strings, or NULL.

Value

If index is NULL, the whole list is returned. Otherwise, if index has length one, the corresponding element is extracted and returned. Otherwise a list containing the requested subset is returned.

Note

This function is not type-safe, in the sense that its return type depends on its arguments. It should therefore be used with care.

Author(s)

Jon Clayden

References

Please cite the following reference when using TractoR in your work:

J.D. Clayden, S. Muñoz Maniega, A.J. Storkey, M.D. King, M.E. Bastin & C.A. Clark (2011). TractoR: Magnetic resonance imaging and tractography with R. Journal of Statistical Software 44(8):1-18. doi:10.18637/jss.v044.i08.