geoscatter

Scatter chart in geographic coordinates

Syntax

geoscatter(lat,lon)

geoscatter(lat,lon,A)

geoscatter(lat,lon,A,C)

geoscatter(___,M)

geoscatter(___,'filled')

geoscatter(___,Name,Value)

geoscatter(gx,___)

s = geoscatter(___)

Description

geoscatter(lat,lon) displays colored circles in a geographic axes at the latitude-longitude locations specified (in degrees) by the vectors lat and lon. lat and lon must be the same size.

geoscatter(lat,lon,A) uses A to specify the area of each marker (in points^2). To draw all the markers with the same size, specify A as a scalar. To draw the markers with different sizes, specify A as a vector the same length as lat and lon. If you do not specify A, geoscatter uses the default size.

geoscatter(lat,lon,A,C) uses C to specify the color of each marker.

geoscatter(___,M) creates a scatter plot where M specifies the marker used. By default, geoscatter uses circles as the marker.

geoscatter(___,'filled') fills the markers.

geoscatter(___,Name,Value) specifies properties of the scatter plot using one or more Name,Value pair arguments. The property settings apply to all the scatter plots.

geoscatter(gx,___) plots into the geographic axes specified by gx instead of into the current axes.

s = geoscatter(___) returns the Scatter object. Use S to modify properties of the object after it is created.

Examples

Create Geographic Scatter Plot Controlling Color, Size, and Shape of Markers

Set up latitude and longitude data.

lon = (-170:10:170);
lat = 50 * cosd(3*lon);

Define data that controls the area of each marker.

A = 101 + 100*(sind(2*lon));

Define data to control the color of each marker.

C = cosd(4*lon);

Plot the data on a geographic scatter plot, specifying the marker size data and the color data. Specify the marker as a triangle, rather than the default circle.

geoscatter(lat,lon,A,C,'^')

Create Geographic Scatter Plot Specifying Basemap

Set up latitude and longitude data.

lon = (-170:10:170);
lat = 50 * cosd(3*lon);

Define the data that controls the area of each marker.

A = 101 + 100*(sind(2*lon));

Define the data that controls the color of each marker.

C = cosd(4*lon);

Create the scatter plot on a set of geographic axes, specifying the marker size data and the color data. The example specifies the marker as a triangle, rather than the default circle.

geoscatter(lat,lon,A,C,'^')

Change the basemap of the geographic scatter plot.

geobasemap colorterrain

Input Arguments

lat — Latitude coordinates in degrees

real, numeric, finite vector within the range [-90 90]

Latitude coordinates in degrees, specified as a real, numeric, finite vector within the range [-90 90]. The vector can contain embedded NaNs. lat must be the same size as lon.

Example: [43.0327 38.8921 44.0435]

Data Types: single | double

lon — Longitude coordinates in degrees

real, numeric, finite vector

Longitude coordinates in degrees, specified as a real, numeric, finite vector. The vector can contain embedded NaNs. lon must be the same size as lat.

Example: [-107.5556 -77.0269 -72.5565]

Data Types: single | double

A — Marker sizes in points squared

36 (default) | scalar | vector | []

Marker sizes in points squared, specified in one of these forms:

• Scalar — Uniform marker size. For example, A = 100 creates all markers with an area of 100 points squared.

• Vector — Different marker size for each data point. The vector must be the same length as lat and lon.

• Empty brackets [] — Default marker size with an area of 36 points squared. Use this option if you want to specify the color input argument, but use the default marker area; for example, geoscatter(lat,lon,[],c).

The SizeData property of the scatter object stores the marker sizes.

Example: 50

Example: [36 25 25 17 46]

C — Marker color

three-column matrix of RGB triplets | vector | RGB triplet | ColorSpec value | ...

Marker color, specified as a MATLAB^® ColorSpec (Color Specification) value, a vector of ColorSpecs, or a three-column matrix of RGB triplets. Use a vector or three-column matrix to specify different marker colors for each data point. When using a vector, geoscatter performs a linear mapping of the values in C to colors in the colormap. Whether specifying a vector or three-column matrix, the vector or matrix must be the same length as lat and lon. If you specify an RGB triplet, the intensities must be in the range [0,1].

Example: 'green'

Example: 'g'

Example: [0 1 0]

When you specify marker colors, geoscatter sets the MarkerFaceColor property of the Scatter object to 'flat' and stores the marker colors in the CData property.

M — Marker symbol

'o' (default) | '+' | '*' | '.' | 'x' | 's' | ...

Marker symbol, specified as a character vector or string containing a marker specifier. For more about marker specifiers, see LineSpec (Line Specification).

When you specify marker type, geoscatter sets the Marker property of the Scatter object.

'filled' — Option to fill the interior of the markers

'filled'

Option to fill the interior of the markers, specified as 'filled'. Use this option with markers that have a face, for example, 'o' or 'square'.

gx — Parent geographic axes object

GeographicAxes object

Parent geographic axes object, specified as a GeographicAxes object.^[1] You can modify the appearance and behavior of a GeographicAxes object by setting its properties. For a list of properties, see GeographicAxes Properties.

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: geoscatter(lat,lon,'filled','MarkerFaceAlpha',.5) creates filled, semi-transparent markers.

The scatter object properties listed here are only a subset. For a complete list, see Scatter Properties.

'Marker' — Marker type

'o' (default) | '+' | '*' | '.' | 'x' | ...

Marker symbol, specified as a character vector or string containing a marker specifier. For more about marker specifiers, see LineSpec (Line Specification).

'MarkerEdgeColor' — Marker outline color

'flat' (default) | 'none' | RGB triplet | ColorSpec value | ...

Marker outline color, specified as 'none','flat', an RGB triplet, or a MATLAB ColorSpec value. The default value of 'flat' uses colors from the CData property.

For a custom color, specify an RGB triplet. An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1]; for example, [0.4 0.6 0.7]. Alternatively, you can specify some common colors by name. This table lists the long and short color name options and the equivalent RGB triplet values.

When you specify marker edge color, geoscatter sets the MarkerEdgeColor property of the Scatter object and stores the marker colors in the CData property.

Example: 'green'

Example: 'g'

Example: [0 1 0]

'MarkerFaceColor' — Marker fill color

'none' (default) | 'flat' | 'auto' | RGB triplet | ColorSpec value | ...

Marker fill color, specified as 'none', 'flat', 'auto', an RGB triplet, or a MATLAB ColorSpec (Color Specification).

• 'flat' — geoscatter uses the CData values.

• 'auto' — geoscatter uses the same color as the Color property for the axes.

Example: [0.3 0.2 0.1]

Example: 'green'

'LineWidth' — Width of marker edge

0.5 (default) | positive value

Width of marker edge, specified as a positive value in point units.

Example: 0.75

Output Arguments

s — Geographic scatter plot

Scatter object

Geographic scatter plot, returned as a Scatter object. Use s to access and modify properties of the geographic scatter plot after it has been created.

Tips

• To customize the geographic axes containing your scatter object, obtain the object's parent, gx = s.Parent, and modify its properties. For a list of properties, see GeographicAxes Properties.

• If you have Mapping Toolbox™, you can specify basemaps of your own choosing by using the addCustomBasemap function.

• When you plot on geographic axes, the geoscatter function assumes that coordinates are referenced to the WGS84 coordinate reference system. If you plot using coordinates that are referenced to a different coordinate reference system, then the coordinates may appear misaligned.