Mapping Toolbox

maptrimp

Trim patch map data to a specified region

Syntax

• [lat,lon] = maptrimp(lat0,lon0,latlim,lonlim)
  

Description

[lat,lon] = maptrimp(lat0,lon0,latlim,lonlim) returns adjusted patch map data sets. The patches must be input in NaN-delimited vectors lat0 and lon0. For any patch face completely outside the specified limits, the entire patch face is discarded. When parts of a patch are outside the limits, those data points are moved to lie on the limits. These limits are specified by the two-element vectors latlim and lonlim, which have the form [south-limit north-limit] and [west-limit east-limit], respectively.

Examples

Make two patches using the scircle1 command, and display them:

• [lat0,lon0] = scircle1([0 0]',[-90 90]',[70 70]');
  axesm('pcarree','Grid','on',...
        'MeridianLabel','on','ParallelLabel','on')
  h = fillm(lat0,lon0,'green');
  
  
  

Now, trim the patch data to lie between 80°S and 45°N latitude, and 120°W and 0° longitude. The patch data is in two columns coming out of scircle1, so first you must turn it into NaN-delimited vectors.

• lat0 = [lat0; NaN NaN];
  lon0 = [lon0; NaN NaN];
  [lat,lon] = maptrimp(lat0(:),lon0(:),[45 -80],[-120 0]);
  clmo(h)
  fillm(lat,lon,'green')
  
  
  

Notice that the patch face to the east, lying completely outside the allowed area, was removed. The western patch was trimmed to the required area.

See Also

maptriml	Trim line vector map data to specified region
maptrims	Trim surface matrix map data to specified region

maptriml

maptrims