To represent a curved surface such as the Earth in two dimensions, you must geometrically transform (literally, and in the mathematical sense, “map”) that surface to a plane. Such a transformation is called a map projection. All map projections intruduce distortion compared to maps on gobes.
The following topics describe the basic properties of map projections, the surfaces onto which projections are developed, the types of parameters associated with different classes of projections, and how projected data can be mapped back to the sphere or spheroid it represents.
Most map projections in the toolbox are implemented as
MATLAB® functions; however, these are only used by certain
calling functions (such as
axesm), and thus
have no documented public API.
|Initialize or reset map projection structure|
|Convert GeoTIFF information to map projection structure|
|Available Mapping Toolbox map projections|
|List available map projections and verify names|
|Project geographic features to map coordinates|
|Unproject features from map to geographic coordinates|
|Map projections supported by projfwd and projinv|
|Direction angle in map plane from azimuth on ellipsoid|
|Azimuth on ellipsoid from direction angle in map plane|
A map projection transforms a curved surface such as the Earth onto a two-dimensional plane.
View a list of the supported Mapping Toolbox™ map projections and their properties.
Map projections are influenced and constrained by five characteristic properties.
Most map projections can be categorized into three families based on the cylinder, cone, and plane geometric shapes.
A projection aspect is the orientation of a map on the page or display screen. An orientation vector controls the map projection aspect.
Variable projection parameters control the appearance of map projections.
An inverse projection transforms plane coordinates to the spherical geographic coordinates.
This example shows how to perform the same projection
computations that are done within Mapping Toolbox display commands
by calling the
All map projections introduce distortions compared to maps on globes. A standard method of visualizing map distortion is to project small circles spaced at regular intervals across the globe.
Compute location-specific map error statistics using