Longitude,Latitude to X,Y

Use the Gravity > Locations > Longitude,Latitude -> X,Y menu option (GRLL2XY GX) to convert longitude/latitude coordinates to X,Y coordinates in either a projected or local coordinate system.

Longitude,Latitude -> X,Y dialog options

Conversion method

Choose the conversion method:

Select Projected coordinate system to use a map projection.

The New Projected Coordinate System dialog opens.
Select Local coordinate system to use a reference location and orientation (origin and azimuth).

The Create Local X,Y from Longitude, Latitude dialog opens (see below).

Script Parameter: GRLL2XY.METHOD

Create Local X,Y from Longitude, Latitude dialog options

Longitude of local (X,Y)	The longitude of the geographic reference location associated with the defined local (X,Y) origin. Script Parameter: LL2XY.LOCLON
Latitude of local (X,Y)	The latitude of the geographic reference location associated with the defined local (X,Y) origin. Script Parameter: LL2XY.LOCLAT
Local X	The local X coordinate of the reference geographic location. Script Parameter: LL2XY.LOCX
Local Y	The local Y coordinate of the reference geographic location. Script Parameter: LL2XY.LOCY
Local length units	The units of the local coordinate system, selected from POSC-compatible abbreviations (for example, "m" or "ft"). Script Parameter: LL2XY.UNITS
Local grid Y direction (deg azimuth)	The azimuth of the local Y-axis, measured clockwise from geographic North. Script Parameter: LL2XY.AZM

Application Notes

This procedure is useful if you have data points with known longitude and latitude coordinates, and you want to work in a projected or local X,Y coordinate system.

Projected coordinate system: For the projected method, the X,Y coordinates are calculated using the selected projected coordinate system.
Local coordinate system: For the local method, the X,Y coordinates are calculated by projecting the longitude/latitude coordinates using a Transverse Mercator projection centered on the specified reference location (defined by the local X,Y coordinates), then rotating the result to the specified Y-axis azimuth.

A local coordinate system is an arbitrary Cartesian coordinate system defined and oriented for the purposes of a particular study.