Display geographic data from display structure
displaym(displaystruct)
displaym(displaystruct,str)
displaym(displaystruct,strings)
displaym(displaystruct,strings,searchmethod)
h = displaym(displaystruct)
displaym(displaystruct) projects
the data contained in the input displaystruct,
a Version 1 Mapping Toolbox™ display structure, in the current
axes. The current axes must be a map axes with a valid map definition.
See the remarks about Version 1 Display Structures below for details on the contents
of display structures.
displaym(displaystruct,str) displays
the vector data elements of displaystruct whose 'tag' fields
contains character vectors beginning with 'str'.
Vector data elements are those whose 'type' field
is either 'line' or 'patch'.
The match is case-insensitive.
displaym(displaystruct,strings) displays
the vector data elements of displaystruct whose 'tag' field
matches with one of the elements (or rows) of strings. strings is
a cell array of character vectors (or a 2-D character array). In the
case of character array, trailing blanks are stripped from each row
before matching.
displaym(displaystruct,strings,searchmethod) controls
the method used to match the values of the tag field
in displaystruct, as follows:
'strmatch' — Search for
matches at the beginning of the tag
'findstr' — Search within
the tag
'exact' — Search for exact
matches
Note that when searchmethod is specified
the search is case-sensitive.
h = displaym(displaystruct) returns
handles to the graphic objects created by displaym.
Note
The type of display structure accepted
by displaym is not the same as a geographic
data structure (geostructs and mapstructs). introduced
in Mapping Toolbox Version 2. Use geoshow or mapshow instead of displaym to
display geostructs or mapstructs—created using shaperead and gshhs,
for example. For more information, see Geographic Data Structures.
The following section documents the contents of display structures.
A display structure is a MATLAB® structure array with the following fields:
A tag field names an individual
feature or object
A type field specifies a MATLAB graphics
object type ('line', 'patch', 'surface', 'text',
or 'light') or has the value 'regular',
specifying a regular data grid
lat and long fields
contain coordinate vectors of latitudes and longitudes, respectively
An altitude field contains a vector
of vertical coordinate values
A string property contains text
to be displayed if type is 'text'
MATLAB graphics properties are specified explicitly,
on a per-feature basis, in an otherproperty field
The choice of options for the type field
reveals that a display structure can contain
Vector geodata (type is 'line' or 'patch')
Raster geodata (type is 'surface' or 'regular')
Graphic objects (type is 'text' or 'light')
The following table indicates which fields are used in the six types of display structures:
Field Name | Type 'light' | Type 'line' | Type 'patch' | Type 'regular' | Type 'surface' | Type 'text' |
|---|---|---|---|---|---|---|
| • | • | • | • | • | • |
| • | • | • | • | • | • |
| • | • | • | • | • | |
| • | • | • | • | • | |
| • | • | ||||
| • | |||||
| • | |||||
| • | |||||
| • | • | • | • | • | • |
| • | • | • | • | • | • |
Some fields can contain empty entries, but each indicated field must exist for the objects in
the structure array to be displayed correctly. For instance, the
altitude field can be an empty matrix and the
otherproperty field can be an empty cell array.
The type field must be one of the specified
map object types: 'line', 'patch', 'regular', 'surface', 'text',
or 'light'.
The tag field must be different from the type field
usually containing the name or kind of map object. Its contents must
not be equal to the name of the object type (i.e., line, surface,
text, etc.).
The lat, long, and altitude fields
can be scalar values, vectors, or matrices, as appropriate for the
map object type.
The map field is a data grid. If map is
a regular data grid, maplegend is its corresponding
referencing vector, and meshgrat is a two-element
vector specifying the graticule mesh size. If map is
a geolocated data grid, lat and long are
the matrices of latitude and longitude coordinates.
The otherproperty field is a cell array containing
any additional display properties appropriate for the map object.
Cell array entries can be a line specification, such as 'r+',
or property name/property value pairs, such as 'color','red'.
If the otherproperty field is left as an empty
cell array, default colors are used in the display of lines and patches
based on the tag field.
Note
In some cases you can use the geoshow function
as a direct alternative to displaym. It accepts
display structures of type line and patch.
extractm | geoshow | mapshow | mlayers | updategeostruct