read_fdg() and read_fgd_dem() always return JGD2011 (SRID: 6668).read_fdg() always return sf object regardless of what kind of file is given (#7).NA_real instead of -9999 (#5).read_fgd_dem()’s handling to fill up missing value cell improvement (@nonsabotage, #3).NEWS.md file to track changes to the package.