User`s guide

R2008a
15-6
To use these options, input angles must be in degrees. That is, angl2str uses the string
units to indicate both the units in which the angle argument is provided and to control
the output format.
This change restores the behavior of angl2str prior to Version 2.6 in a slightly different
form. Before V. 2.6, the DM and DMS options were specified by a units strings of 'dm'
and 'dms', respectively. The new strings that replace them signify that the functions
degrees2dm and degrees2dms, introduced in Version 2.5 (R2007a), perform the
conversions of inputs given in degrees to DM and DMS notation.
New Longitude-Wrapping Option in the closePolygonParts Utility
The closePolygonParts function now accepts an optional third argument,
angleunits, that must be string-valued and can be either 'degrees' or 'radians'.
If you include this argument with a value appropriate for the first two (lat, lon)
arguments, closePolygonParts can correctly account for longitude wrapping. For
example, a polygon that begins at a given latitude with a longitude of -180 degrees, and
ends at the same latitude with a longitude of 180 degrees is regarded as closed and an
additional vertex is not added.
Changes to Terminology for Geographic Data Structures
From Version 2.0 onward, the Mapping Toolbox documentation has referred to “version 1
geographic data structures” and “version 2 geographic data structures,” using the terms
“geostruct1” and “geostruct2” respectively as shorthand for them. To reflect current
usage, starting with this version of the toolbox, these terms are obsolete; new terms and
distinctions have been defined to help clarify what these structures are and can be used
for:
• Geographic data structure arrays, introduced in Version 2.0, contain vector features
and are called either
• Geostructs, if they contain geographic coordinates (latitudes and longitudes)
• Mapstructs, if they contain projected map/planar coordinates (x and y)
• Display structure arrays, dating from Version 1, also used to be called geographic data
structures, and can contain either vector features or raster geodata.
Due to their greater generality, geostructs and mapstructs are the preferred form in
which to represent vector features in the toolbox. The preferred way to package raster
geodata is with regular or geolocated data grids (2-D numeric arrays accompanied by