For spatial data read into a data frame with longitude and latitude specified for each observation, this function aggregates data to a new set of longitude/ latitude combinations, i.e., to a new grid. This effectively takes the mean across all gridcells that have their mid-point within the coarse-resolution gridcell and without area-weighing of constituent (fine-resolution) gridcells.
regrid_df(df, res, lon_start, lon_end, lat_start, lat_end, varnam = NA)Arguments
- df
A data frame. Must have columns named
'lon'and'lat'.- res
Resolution of the new grid in decimal degrees
- lon_start
The left (west) margin of the first (western-most) gridcell along longitudes.
- lon_end
The right (east) margin of the first (eastern-most) gridcell along longitudes.
- lat_start
The lower (south) margin of the first (southern-most) gridcell along latitudes
- lat_end
The upper (north) margin of the first (northern-most) gridcell along latitudes
- varnam
A character string specifying the variable name in the data frame. When not specified, regrids all numeric variables.
Value
A data frame