== [InternalDocumentation Internal Documentation]/[wiki:Classes Classes] == ----- = Class Geo_reference = Defined in file coordinate_transforms/geo_reference.py. == Discussion == == Class Attributes == || '''zone''' || The UTM zone the Geo_reference is based in. || || '''false_easting''' || ?? || || '''false_northing''' || ?? || || '''datum''' || The datum used (default is 'wsg84'). || || '''projection''' || The projection used (default is 'UTM'). || || '''units''' || The units of measure used (default is metres, 'm'). || || '''xllcorner''' || The X coordinate of origin (default is 0.0 with respect to the UTM grid origin). || || '''yllcorner''' || The Y coordinate of origin (default is 0.0 with respect to the UTM grid origin). || == Class Methods == || '''get_xllcorner(self)''' || Returns the '''.xllcorner''' attribute. || || '''get_yllcorner(self)''' || Returns the '''.yllcorner''' attribute. || || '''get_zone(self)''' || Returns the '''.zone''' attribute. || || '''write_NetCDF(self, outfile)''' || Write '''Geo_reference''' attributes to an open NetCDF file at `outfile`. The attributes written are '''.xllcorner''', '''.yllcorner''', '''.zone''', '''.false_easting''', '''false_northing''', '''.datum''', '''.projection''' and '''.units'''. || || '''read_NetCDF(self, infile)''' || Read '''Geo_reference''' attributes from an open NetCDF file at `infile`. The attributes read are '''.xllcorner''', '''.yllcorner''', '''.zone''', '''.false_easting''', '''false_northing''', '''.datum''', '''.projection''' and '''.units'''. || || '''write_ASCII(self, fd)''' || Write '''Geo_reference''' attributes to an open ASCII file at `fd`. The attributes written are '''.zone''', '''.xllcorner''' and '''.yllcorner'''. || || '''read_ASCII(self, fd, read_title=None)''' || Read '''Geo_reference''' attributes from an open ASCII file at `fd`. The attributes read are '''.zone''', '''.xllcorner''' and '''.yllcorner'''. If `read_title` is `None` then we expect the title line in the data file to match the standard title in the first two characters. Otherwise `read_title` is the __assumed__ title in the file which must match the standard title in the first two characters, and the title line is not read from the file. || || '''change_points_geo_ref(self, points, points_geo_ref=None)''' || Change the coordinates of a list or array of Points to be relative to a new '''Geo_reference'''. The new Point data is returned. Note that the input Point is __also__ changed. If `points_geo_ref` is None then the coordinates are changed to be absolute with respect to the current '''Geo_reference'''. || || '''is_absolute(self)''' || Returns True if the '''Geo_reference''' origin is close to the UTM origin. || || '''get_absolute(self, points)''' || Given a list (or array) of Points geo-referenced to this '''Geo_reference''', return a list (or array) of Points with absolute coordinates (ie, relative to the UTM origin). Note: also changes the input Point list! The inverse of '''get_relative()'''. || || '''get_relative(self, points)''' || Given a list (or array) of Points geo-referenced to this '''Geo_reference''', return a list (or array) of Points with relative coordinates (ie, relative to the '''Geo_reference''' origin). Note: also changes the input Point list! The inverse of '''get_absolute()'''. || || '''reconcile_zones(self, other)''' || Compare two '''Geo_reference''' instances and reconcile the '''.zone''' attributes. If either instance (but not both) have a '''.zone''' of DEFAULT_ZONE then copy the '''.zone''' attribute from the instance with a real zone. Note: if `other` is None then assume a default '''Geo_reference''' instance. || || '''get_origin(self)''' || Returns a tuple of ('''.zone''', '''.xllcorner''', '''.yllcorner''') for the instance. Note: should use this method and delete methods '''get_xllcorner()''', '''get_yllcorner()''' and '''get_zone()'''. || || '''_ _cmp_ _(self, other)''' || Allows python code to directly compare two '''Geo_reference''' instances. Two instances are equal if their '''.zone''', '''.xllcorner''' and '''yllcorner''' attributes are the same. || == Notes == There is a lot of room for error in handling '''Point''' and '''Geo_reference''' instances. The '''Geo_spatial''' class includes instances of these two classes. This class is defined in the 'old' way. Needs to be changed to the new method before moving to python 2.6. ----- == [InternalDocumentation Internal Documentation]/[wiki:Classes Classes] ==