spans_to_viscell: Transform a vector of spans (with duplication) into a visibility vector
Description
Transform a vector of spans (with duplication) into a visibility vector
Usage
spans_to_viscell(spans)
Value
A logical vector the same length as spans indicating whether the contents of a string vector
with those spans is valid.
Arguments
spans
(numeric) a vector of spans, with each span value repeated
for the cells it covers.
Details
The values of spans are assumed to be repeated such that each individual position covered by the
span has the repeated value.
This means that each block of values in spans must be of a length at least equal to its value
(i.e. two 2s, three 3s, etc).
This function correctly handles cases where two spans of the same size are next to each other;
i.e., a block of four 2s represents two large cells each of which spans two individual cells.