Introduction to Mapping Graphics
Even though geospatial data often is manipulated and analyzed without being displayed, high-quality interactive cartographic displays can play valuable roles in exploratory data analysis, application development, and presentation of results.
Using Mapping Toolbox™ capabilities, you can display geographic information almost as easily as
you can display tabular or time-series data in MATLAB® plots. Most mapping functions are similar to MATLAB plotting functions, except they accept data with geographic/geodetic
coordinates (latitudes and longitudes) instead of Cartesian and polar coordinates.
Mapping functions typically have the same names as their MATLAB counterparts, with the addition of an 'm'
suffix (for
maps). For example, the Mapping Toolbox analog to the MATLAB
plot
function is plotm
.
Mapping Toolbox software manages most of the details in displaying a map. It projects your data, cuts and trims it to specified limits, and displays the resulting map at various scales. With the toolbox you can also add customary cartographic elements, such as a frame, grid lines, coordinate labels, and text labels, to your displayed map. If you change your projection properties, or even the projection itself, some Mapping Toolbox map displays are automatically redrawn with the new settings, undoing any cuts or trims if necessary.
The toolbox also makes it easy to modify and manipulate maps. You can modify the map display and mapped objects either from the command line or through property editing tools you can invoke by clicking on the display.
Note
In its current implementation, the toolbox maintains the map projection and
display properties by storing special data in the UserData
property of the axesm
-based map. The toolbox also takes over
the UserData
property of objects projected on
axesm
-based maps. Therefore, never attempt to set the
UserData
property of an axesm
-based
map or an object projected onto an axesm
-based map. Do not
apply the MATLAB
get
function to axes UserData
, depend on
the contents of UserData
in any way, or apply functions that
set or get UserData
to the axesm
-based map
or the objects mapped on an axesm
-based map. Only use the
Mapping Toolbox functions getm
and setm
to obtain and modify the properties of
axesm
-based maps.