bounds

Bounds of shape in geographic or planar coordinates

Since R2024b

Syntax

[latlim,lonlim] = bounds(geoshp)

[latlim,lonlim] = bounds(geoshp,"all")

[xlimits,ylimits] = bounds(mapshp)

[xlimits,ylimits] = bounds(mapshp,"all")

Description

Geographic Coordinates

[latlim,lonlim] = bounds(geoshp) calculates the latitude and longitude limits of the smallest quadrangle that encloses each specified shape in geographic coordinates.

[latlim,lonlim] = bounds(geoshp,"all") calculates the limits over all the specified shapes.

Planar Coordinates

[xlimits,ylimits] = bounds(mapshp) calculates the xy-limits of the smallest rectangle that encloses each specified shape in planar coordinates.

[xlimits,ylimits] = bounds(mapshp,"all") calculates the limits over all the specified shapes.

Examples

Calculate Bounds of Shape in Geographic Coordinates

Calculate the bounds of shapes in geographic coordinates. When you pass geographic shapes to the bounds function, the function calculates latitude and longitude limits.

Read a shapefile of US states into the workspace as a geospatial table. The table represents the states using polygon shapes in geographic coordinates. Extract the polygon shapes.

states = readgeotable("usastatehi.shp");
geoshp = states.Shape

geoshp=51×1 geopolyshape array with properties:
              NumRegions: [51×1 double]
                NumHoles: [51×1 double]
                Geometry: "polygon"
    CoordinateSystemType: "geographic"
           GeographicCRS: [1×1 geocrs]
      ⋮

Find the bounds of each polygon shape. By default, the function returns a set of latitude and longitude limits for each shape object.

[latlim,lonlim] = bounds(geoshp);

Store the latitude and longitude limits in the geospatial table by creating new table variables.

states.LatitudeLimits = latlim;
states.LongitudeLimits = lonlim;

View the first eight rows of the table. Note that each shape object has a corresponding set of latitude and longitude limits.

head(states)

       Shape            Name         LabelLat    LabelLon     LatitudeLimits      LongitudeLimits  
    ____________    _____________    ________    ________    ________________    __________________

    geopolyshape    "Alabama"         32.283     -86.921     30.221    35.008    -88.473    -84.889
    geopolyshape    "Alaska"           64.61     -152.46     51.217    71.333    -187.54    -130.03
    geopolyshape    "Arizona"         34.345     -112.07     31.332    37.004    -114.81    -109.04
    geopolyshape    "Arkansas"        34.835     -91.886     33.004    36.499    -94.618    -89.645
    geopolyshape    "California"      36.822     -119.66     32.535     42.01    -124.41    -114.13
    geopolyshape    "Colorado"         39.03     -105.54     36.992    41.003    -109.06    -102.04
    geopolyshape    "Connecticut"     41.511     -72.763     40.986     42.05    -73.728    -71.787
    geopolyshape    "Delaware"        39.107     -75.494     38.452    39.838    -75.789    -75.049

Calculate Bounds of Shape in Planar Coordinates

Calculate the bounds of shapes in planar coordinates. When you pass planar shapes to the bounds function, the function calculates xy-limits.

Read hydrography data for an area in Concord, MA as a geospatial table. The table represents the states using polygon shapes in planar coordinates. Extract the polygon shapes.

hydro = readgeotable("concord_hydro_area.shp");
mapshp = hydro.Shape

mapshp=98×1 mappolyshape array with properties:
              NumRegions: [98×1 double]
                NumHoles: [98×1 double]
                Geometry: "polygon"
    CoordinateSystemType: "planar"
            ProjectedCRS: [1×1 projcrs]
      ⋮

Find the bounds of each polygon shape. By default, the function returns a set of xy-limits for each shape object.

[xlimits,ylimits] = bounds(mapshp);

Store the xy-limits in the geospatial table by creating new table variables.

hydro.XLimits = xlimits;
hydro.YLimits = ylimits;

View the first eight rows of the table. Note that each shape object has a corresponding set of xy-limits.

head(hydro)

       Shape           AREA       PERIMETER            XLimits                     YLimits         
    ____________    __________    _________    ________________________    ________________________

    mappolyshape        2456.4     289.22      2.0759e+05    2.0763e+05    9.1336e+05    9.1349e+05
    mappolyshape    1.2685e+05      11264      2.0748e+05    2.1032e+05    9.1101e+05    9.1344e+05
    mappolyshape        2075.4     207.37      2.0763e+05    2.0767e+05    9.1321e+05     9.133e+05
    mappolyshape        814.05     117.55      2.0927e+05    2.0931e+05    9.1325e+05    9.1329e+05
    mappolyshape         10754     633.93      2.0861e+05    2.0882e+05    9.1309e+05    9.1326e+05
    mappolyshape        5894.2     370.54      2.1023e+05    2.1032e+05    9.1309e+05    9.1323e+05
    mappolyshape         48368     3378.7      2.0657e+05    2.0743e+05    9.1241e+05    9.1318e+05
    mappolyshape         27673     1650.6      2.0707e+05    2.0746e+05    9.1272e+05    9.1318e+05

Calculate Bounds Over All Shapes

By default, when you pass multiple shapes to the bounds function, the function calculates a set of bounds for each shape object. Calculate the bounds over all the shapes by using the "all" option.

Read a shapefile containing the coordinates of locations in Boston as a geospatial table. The table represents the locations using point shapes in geographic coordinates. Extract the point shapes.

places = readgeotable("boston_placenames.gpx");
geoshp = places.Shape

geoshp = 
  13×1 geopointshape array with properties:

               NumPoints: [13×1 double]
                Latitude: [13×1 double]
               Longitude: [13×1 double]
                Geometry: "point"
    CoordinateSystemType: "geographic"
           GeographicCRS: [1×1 geocrs]

Find the bounds over all the point shapes.

[latlim,lonlim] = bounds(geoshp,"all")

latlim = 1×2

   42.3459   42.3668

lonlim = 1×2

  -71.0995  -71.0495

Input Arguments

geoshp — Shape in geographic coordinates

geopointshape, geolineshape, or geopolyshape object | vector of geopointshape, geolineshape, or geopolyshape objects

Shape in geographic coordinates, specified as a geopointshape, geolineshape, or geopolyshape object or as a vector of geopointshape, geolineshape, or geopolyshape objects. When you specify an array, you can include a combination of point, line, and polygon shape objects.

mapshp — Shape in planar coordinates

mappointshape, maplineshape, or mappolyshape object | vector of mappointshape, maplineshape, or mappolyshape objects

Shape in geographic coordinates, specified as a mappointshape, maplineshape, or mappolyshape object or as a vector of mappointshape, maplineshape, or mappolyshape objects. When you specify an array, you can include a combination of point, line, and polygon shape objects.

Output Arguments

latlim — Latitude limits

two-column matrix

Latitude limits, returned as a two-column matrix. The first column of the matrix contains the northern latitude limits, and the second column of the matrix contains the southern latitude limits. For each row of the matrix, the first limit is less than or equal to the second limit.

When you do not specify the "all" option, the number of rows in the matrix matches the number of shapes in geoshp. When you do specify the "all" option, the matrix has one row.

The units of latlim match the units of geoshp. If the GeographicCRS property of geoshp contains a geocrs object, you can find the units by querying the AngleUnit property of the geocrs object, for example geoshp.GeographicCRS.AngleUnit.

lonlim — Longitude limits

two-column matrix

Longitude limits, returned as a two-column matrix. The first column of the matrix contains the western longitude limits, and the second column of the matrix contains the eastern longitude limits. For each row of the matrix, the first limit is less than or equal to the second limit.

When you do not specify the "all" option, the number of rows in the matrix matches the number of shapes in geoshp. When you do specify the "all" option, the matrix has one row.

The units of lonlim match the units of geoshp. If the GeographicCRS property of geoshp contains a geocrs object, you can find the units by querying the AngleUnit property of the geocrs object, for example geoshp.GeographicCRS.AngleUnit.

xlimits — x-limits

two-column matrix

x-limits, returned as a two-column matrix. The first column of the matrix contains the lower x-limits, and the second column of the matrix contains the upper x-limits. For each row of the matrix, the first limit is less than or equal to the second limit.

When you do not specify the "all" option, the number of rows in the matrix matches the number of shapes in mapshp. When you do specify the "all" option, the matrix has one row.

The units of xlimits match the units of mapshp. If the ProjectedCRS property of mapshp contains a projcrs object, you can find the units by querying the LengthUnit property of the projcrs object, for example mapshp.ProjectedCRS.LengthUnit.

ylimits — y-limits

two-column matrix

y-limits, returned as a two-column matrix. The first column of the matrix contains the lower y-limits, and the second column of the matrix contains the upper y-limits. For each row of the matrix, the first limit is less than or equal to the second limit.

When you do not specify the "all" option, the number of rows in the matrix matches the number of shapes in mapshp. When you do specify the "all" option, the matrix has one row.

The units of ylimits match the units of mapshp. If the ProjectedCRS property of mapshp contains a projcrs object, you can find the units by querying the LengthUnit property of the projcrs object, for example mapshp.ProjectedCRS.LengthUnit.

Version History

Introduced in R2024b