Feature request: allow for unequal sampling areas

[joelnitta]

Currently, it is assumed that all sites (cells of the community data matrix) have equal area (size) and therefore weighing by area can be done simply by using the number of sites. But this may not be true of all datasets.

This was originally pointed out by Hong Qian @ISMRCC via email:

Species range size is measured by the number of sampling units in canaper. This is sufficient for equal-area sampling units. However, for unequal-area sampling units, one might measure species range size in two ways: the number of sampling units, and the total area of sampling units, as in the papers DOI: 10.1111/geb.13001 and https://doi.org/10.1101/2022.12.28.522105. Would it be possible to make canaper to be able to calculate phylogenetic endemism metrics using both types of species range size? Because many data species sets are for unequal-area geographic units, such a modification in canaper would make the package more widely used.