spatstat (version 1.23-1)

Extract.fasp: Extract Subset of Function Array

Description

Extract a subset of a function array (an object of class "fasp").

Usage

## S3 method for class 'fasp':
[(x, I, J, drop=TRUE,\dots)

Arguments

x

A function array. An object of class "fasp".

I

any valid expression for a subset of the row indices of the array.

J

any valid expression for a subset of the column indices of the array.

drop

Logical. When the selected subset consists of only one cell of the array, if drop=FALSE the result is still returned as a $1 \times 1$ array of functions (class "fasp") while if drop=TRUE it i

...

Ignored.

Value

• A function array (of class "fasp"). Exceptionally, if the array has only one cell, and if drop=TRUE, then the result is a function value table (class "fv").

Details

A function array can be regarded as a matrix whose entries are functions. See fasp.object for an explanation of function arrays.

This routine extracts a sub-array according to the usual conventions for matrix indexing.

See Also

fasp.object

Examples

# Lansing woods data - multitype points with 6 types
 data(lansing)
 <testonly># smaller dataset
   lansing <- lansing[ seq(1,lansing$n,by=45), ]</testonly>
 # compute 6 x 6 array of all cross-type K functions
 a <- alltypes(lansing, "K")

 # extract first three marks only
 b <- a[1:3,1:3]
 plot(b)
 # subset pertaining to hickories
 h <- a[levels(lansing$marks) == "hickory", ]
 plot(h)