meshm

Project regular data grid on axesm-based map

Syntax

meshm(Z,R)

meshm(Z,R,gratsize)

meshm(Z,R,gratsize,h)

meshm(___,Name,Value)

s = meshm(___)

Description

meshm(Z,R) displays a surface on the current axesm-based map by warping the regular data grid specified by Z, with spatial reference R, to a projected graticule mesh. The color of the surface varies according to the values in Z. This syntax displays the surface in a horizontal plane with all height values set to 0.

meshm(Z,R,gratsize) specifies the size of the graticule mesh as gratsize.

meshm(Z,R,gratsize,h) displays the surface using the heights specified by h.

meshm(___,Name,Value) specifies surface properties using one or more name-value pair arguments. For example, "FaceAlpha",0.5 creates a semitransparent plot.

s = meshm(___) returns the primitive surface object. Use s to modify the plot after creation. For a list of properties, see Surface Properties.

Examples

Display Regular Data Grid on axesm-Based Map

Load elevation data and a geographic cells reference object for the Korean peninsula. Then, display the data on a world map using a colormap appropriate for elevation data.

load korea5c
worldmap(korea5c,korea5cR)
meshm(korea5c,korea5cR)
demcmap(korea5c)

Display Surface in 3-D

Read elevation data and a geographic postings reference object for a region around South Boulder Peak in Colorado. Crop the data to cover a smaller region.

[Z,R] = readgeoraster("n39_w106_3arc_v2.dt1","OutputType","double");
[Z,R] = geocrop(Z,R,[39.5 39.7],[-105.9 -105.7]);

Display the data as a surface by specifying the graticule size as the size of the raster (R.RasterSize) and the height data as the elevation data (Z). Apply a colormap appropriate for elevation data.

usamap(Z,R)
meshm(Z,R,R.RasterSize,Z)
demcmap(Z)

View the region in 3-D.

view(3)

Modify Appearance of Surface Plot

Load world elevation data as an array and a geographic cells reference object. Then, display the data on a world map. Adjust the transparency of the surface plot using the FaceAlpha name-value argument.

load topo60c
worldmap(topo60c,topo60cR)
meshm(topo60c,topo60cR,"FaceAlpha",0.5)

Apply a colormap appropriate for elevation data.

demcmap(topo60c)

Input Arguments

Z — Regular data grid

m-by-n array

Regular data grid, specified as an m-by-n array.

R — Spatial reference for Z

GeographicCellsReference object | GeographicPostingsReference object

Spatial reference for Z, specified as a GeographicCellsReference or GeographicPostingsReference object. The RasterSize property of R must be consistent with size(Z).

gratsize — Graticule size

[50 100] (default) | two-element vector | []

Graticule size, specified as one of these options:

• A two-element vector, where the first element indicates the number of parallels and the second element indicates the number of meridians.

• [], which specifies the default graticule size of [50 100]. Use this option when you want to use the default graticule size and specify the h argument.

h — Surface height

scalar | matrix of size gratsize

Surface height, specified as a scalar or a matrix of size gratsize.

• When you specify a scalar, the meshm function displays the grid in the horizontal plane with all height values set to h.

• When you specify a matrix of size gratsize, the meshm function displays each vertex of the graticule mesh at the corresponding height in h.

When the MapProjection property of the axesm-based map is "globe", h is referenced to the ellipsoid.

Data Types: double

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: meshm(Z,R,LineStyle="-") displays the graticule mesh using solid lines.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: meshm(Z,R,"LineStyle","-") displays the graticule mesh using solid lines.

Note

Use name-value arguments to specify values for the properties of the Surface object created by this function. The properties listed here are only a subset. For a full list, see Surface Properties.

Surface objects created by the meshm function have these limitations:

• Setting the XData, YData, and ZData properties of the surface object is not supported.

• If you set the UserData property of the surface and then change the projection of the axesm-based map, MATLAB^® does not reproject the surface.

LineStyle — Line style

"none" (default) | "-" | "--" | ":" | "-."

Line style, specified as one of the options listed in this table.

Line Style	Description	Resulting Line
"-"	Solid line
"--"	Dashed line
":"	Dotted line
"-."	Dash-dotted line
"none"	No line	No line

LineWidth — Line width

0.5 (default) | positive value

Line width, specified as a positive value in points, where 1 point = 1/72 of an inch. If the line has markers, then the line width also affects the marker edges.

The line width cannot be thinner than the width of a pixel. If you set the line width to a value that is less than the width of a pixel on your system, the line displays as one pixel wide.

Output Arguments

s — Primitive surface object

Surface object

Primitive surface object, returned as a Surface object. Use s to modify the Surface object after creation. For a list of properties, see Surface Properties.

Surface objects created by the meshm function have these limitations:

• Setting the XData, YData, and ZData properties of the surface object is not supported.

• If you set the UserData property of the surface and then change the projection of the axesm-based map, MATLAB does not reproject the surface.

Tips

• The FaceColor property of the surface object depends on the size of the graticule mesh. The meshm function sets FaceColor to "flat" when the size of the graticule mesh matches the size of Z, and "texturemap" otherwise.

• The meshm function projects the graticule mesh using the projection specified by the MapProjection property of the axesm-based map. To improve the resolution of the plot, increase the size of the graticule mesh. Increasing the size of the graticule mesh can increase the amount of time MATLAB requires to display the surface.

Version History

Introduced before R2006a

R2024b: meshm does not accept referencing vectors or referencing matrices as input

The meshm function does not accept referencing vectors or referencing matrices as input. Use a geographic raster reference object, specified as a GeographicCellsReference or GeographicPostingsReference object, as input instead. Reference objects have several advantages over referencing vectors and referencing matrices.

• Unlike referencing vectors and referencing matrices, reference objects have properties that document the size of the associated raster, its geographic limits, and the direction of its rows and columns.

• You can manipulate the limits of geographic rasters associated with reference objects using the geocrop function.

• You can manipulate the size and resolution of geographic rasters associated with reference objects using the georesize function.

To update your code, create a geographic reference object.

• Create a geographic reference object for a raster of cells by using the georefcells function.

• Create a geographic reference object for a raster of regularly posted samples by using the georefpostings function.

• Convert from a referencing vector to a geographic reference object by using the refvecToGeoRasterReference function.

• Convert from a referencing matrix to a geographic reference object by using the refmatToGeoRasterReference function.

Once you have created a reference object, replace uses of the referencing vector or referencing matrix in your code with the reference object.

R2023b: meshm will not accept referencing vectors or referencing matrices as input

When you specify a referencing vector or referencing matrix as input, the meshm function issues a warning that it will not accept referencing vectors or referencing matrices as input in a future release.