


IDL> map=obj_new('map')                  ;-- create map instance

IDL> map->read,file                      ;-- read file

IDL> map->plot                           ;-- plot map

IDL> dmap=map->drotate(duration,/days)   ;-- differentially rotate 'duration' days

IDL> rmap=map->rotate(angle)             ;-- roll rotate 'angle' degrees

IDL> fmap=map->extract(xrange=xrange,yrange=yrange)  ;-- extract subfield

IDL> smap=map->get(/map)                 ;-- extract map structure