Convert Longitude 0-360 to -180 to 180 or 180W-180E in fortran and matlab, transform lat lon coordinates

Variables in explanation
long1 is the longitude varying from -180 to 180 or 180W-180E
long3 is the longitude variable from 0 to 360 (all positive)

To convert longitude from (0-360) to (-180 to 180)

Matlab and fortran
long1=mod((long3+180),360)-180

Matlab
long1=rem((long3+180),360)-180

Fortran
long1=modulo((long3+180),360)-180


To convert longitude from (-180 to 180) to (0-360)

Matlab
lon3=mod(lon1,360)

Fortran
lon3=modulo(lon1,360)


The “mod” function is Fortran is equivalent to “rem” function in Matlab.

The “modulo” function in Fortran is equivalent to “mod” function in Matlab.