verbalogic {spatstat.utils}R Documentation

Verbal Logic

Description

Perform the specified logical operation on the character vector x, recognising the special strings "TRUE" and "FALSE" and treating other strings as logical variables.

Usage

verbalogic(x, op = "and")

Arguments

x

Character vector.

op

Logical operation: one of the character strings "and", "or" or "not".

Details

This function performs simple logical operations on character strings that represent human-readable statements.

The character vector x may contain any strings: the special strings "TRUE" and "FALSE" are treated as the logical values TRUE and FALSE, while all other strings are treated as if they were logical variables.

If op="and", the result is a single string, logically equivalent to x[1] && x[2] && ... && x[n]. First, any entries of x equal to "TRUE" are removed. The result is "FALSE" if any of the entries of x is "FALSE"; otherwise it is equivalent to paste(x, collapse=" and ").

If op="or", the result is a single string, logically equivalent to x[1] || x[2] || ... || x[n]. First, any entries of x equal to "FALSE" are removed. The result is "TRUE" if any of the entries of x is "TRUE"; otherwise it is equivalent to paste(x, collapse=" or ").

If op="not", the result is a character vector y such that y[i] is the logical negation of x[i].

The code does not understand English grammar and cannot expand logical expressions.

Value

A character string.

Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au.

Examples

   x <- c("The sky is blue", "my name is not Einstein", "FALSE")
   verbalogic(x, "and")
   verbalogic(x, "or")
   verbalogic(x, "not")

[Package spatstat.utils version 3.0-5 Index]