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tbase

Read 5-minute global terrain elevations from TerrainBase

Syntax

[Z,refvec] = tbase(scalefactor)
[Z,refvec] = tbase(scalefactor,latlim,lonlim)

Description

[Z,refvec] = tbase(scalefactor) reads the data for the entire world, reducing the resolution of the data by the specified scale factor. The result is returned as a regular data grid and an associated three-element referencing vector.

[Z,refvec] = tbase(scalefactor,latlim,lonlim) reads the data for the part of the world within the latitude and longitude limits. The limits must be two-element vectors in units of degrees.

Background

TerrainBase is a global model of terrain and bathymetry on a regular 5-minute grid (approximately 10 km resolution). It is a compilation of the public domain data from almost 20 different sources, including the DCW-DEM and ETOPO5. The data set was created by the National Geophysical Data Center and World Data Center-A for Solid Earth Geophysics in Boulder, Colorado.

    Note   For details on locating map data for download over the Internet, see the following documentation at the MathWorks Web site: Finding Geospatial Data.

Examples

expand all

Read Data for the Entire World But Read Every 10th Point

Set the scale factor to read every 10th point.

scalefactor = 10;

Read the data and view the size of the returned variables.

[Z,refvec] = tbase(scalefactor);
whos Z refvec 
Name              Size         Bytes  Class

 Z               216x432       746496  double array
 refvec            1x3             24  double array

Determine the latitude and longitude limits of the geographic quadrangle bounding the data grid.

limitm(Z,refvec)
ans =

          -90           90         -180          180

Read Data for a Region at Full Resolution

Set the scale factor to 1 and set the longitude and latitude limits. This example reads the data for Korea and Japan.

scalefactor = 1;
latlim = [30 45];
lonlim = [115 145];

Read the data and view the size of the returned variables.

[Z,refvec] = tbase(scalefactor,latlim,lonlim);
whos
Name       Size         Bytes  Class

 Z        180x360       518400  double array
 refvec     1x3             24  double array

See Also

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