Changes in version 0.4.0 (2021-10-20)                  

    o   static pdf vignette to avoid problems with CRAN check

    o   direct support for sf objects (spatial vector data)

                 Changes in version 0.3.1 (2021-09-27)                  

    o   NAs are now handled correctly and don't cause errors

    o   fixed errors in spatial section of vignette

                 Changes in version 0.3.0 (2021-09-22)                  

    o   Initial release