SP_PROJ converts between geographic (latitude and longitude) and US state plane coordinates. SP_PROJ can perform both forward (from geographic to state plane) and inverse transformations (from state plane to geographic). All US state plane zones are included except for Alaska. Calculations assume the NAD83 datum and GRS1980 spheriod.
Mapping toolbox is required. SP_PROJ creates the map structure for the specified US state plane zone and passes it to either PROJFWD and PROJINV to perform the coordinate transformations.
lat = 37.45569;
lon = -122.17009;
% Calculate the x,y, coordinates in survey feet
% in the 'California 1' state plane zone.
[xsp,ysp] = sp_proj('california 1','forward',lon,lat,'sf')
% Re-calculate the geographic coordinates
% also output the map structure as optional 3rd output
[lon1,lat1,mstruct] = sp_proj('california 1','inverse',xsp,ysp,'sf')
fixed output order for inverse calculation