Convert CalCOFI line/station to longitude/latitude

The CalCOFI station plan is a coordinate system in its own right, and PROJ ships it as +proj=calcofi — so this is a projection, not a lookup against grid. That distinction matters: a lookup only resolves stations that exist in the grid table, while the transform resolves any line/station pair, including the historical inshore stations and the Gulf of California and Baja lines that the modern pattern dropped.

Usage

cc_calcofi_to_lonlat(line, station)

Arguments

line, station

numeric vectors of CalCOFI line and station, recycled to a common length. NA in either yields NA in both outputs.

Value

a data.frame with longitude and latitude (WGS 84), one row per input

Details

Use it to recover a position for a row that records where it was in CalCOFI terms but carries no lon/lat. Once a position exists, hex_id and grid_key follow from it in the usual way (.hex_expr(), assign_grid_key()), so a recovered row becomes a full participant in spatial rollups rather than an ungridded remainder.

Examples

if (FALSE) { # \dontrun{
cc_calcofi_to_lonlat(90, 60)   # -119.96, 32.42 — off San Diego
} # }