Legend Properties

Location with respect to the axes, specified as one of the location values listed in this table.

Example: legend('Location','northeastoutside')

Orientation, specified as one of these values:

Example: legend('Orientation','horizontal')

Number of columns, specified as a positive integer. If there are not enough legend items to fill the specified number of columns, then the number of columns that appear might be fewer.

Use the Orientation property to control whether the legend items appear in order along each column or along each row.

Example: lgd.NumColumns = 3

Selection mode for the NumColumns value, specified as one of these values:

Order of legend items, specified as one of the values in this table.

For most charts, the default direction is "normal". However, for stacked bar and area charts, the default direction is "reverse" to match the stacking order of the chart.

Selection mode for the Direction value, specified as one of these values:

Horizontal space for legend icons, specified as a positive number in point units, where 1 point is 1/72 inch. Use this property when you want to customize the amount of space around the legend icons. Smaller values shorten the widths of certain icons, which results in less white space and a narrower legend box.

For example, here are three legends that are the same except for their IconColumnWidth values (30, 40, and 10 respectively).

lgd.IconColumnWidth = lgd.FontSize;

Control how the IconColumnWidth property is set, specified as one of these values:

If you set the value of the IconColumnWidth property manually, MATLAB changes the value of the IconColumnWidthMode property to "manual".

Custom location and size, specified as a four-element vector of the form [left bottom width height]. The first two values, left and bottom, specify the distance from the lower left corner of the figure to the lower left corner of the legend. The last two values, width and height, specify the legend dimensions. The Units property determines the position units.

If you specify the Position property, then MATLAB automatically changes the Location property to 'none'.

Example: legend({'A','B'},'Position',[0.2 0.6 0.1 0.2])

Position units, specified as one of the values in this table.

All units are measured from the lower-left corner of the container window.

This property affects the Position property. If you change the units, then it is good practice to return it to its default value after completing your computation to prevent affecting other functions that assume Units is the default value.

If you specify the Position and Units properties as Name,Value pairs when creating the object, then the order of specification matters. If you want to define the position with particular units, then you must set the Units property before the Position property.

Layout options, specified as a TiledChartLayoutOptions object. This property is useful when the legend is in a tiled chart layout.

To position the legend within the grid of a tiled chart layout, set the Tile property on the TiledChartLayoutOptions object. For example, consider a 3-by-3 tiled chart layout. The layout has a grid of tiles in the center, and four tiles along the outer edges. In practice, the grid is invisible and the outer tiles do not take up space until you populate them with axes or other objects.

This code places the legend lgd in the third tile of the grid..

lgd.Layout.Tile = 3;

To place the legend in one of the surrounding tiles, specify the Tile property as 'north', 'south', 'east', or 'west'. For example, setting the value to 'east' places the legend in the tile to the right of the grid.

lgd.Layout.Tile = 'east';

If the legend is not a child of a tiled chart layout (for example, if it is a child of the figure) then this property is empty and has no effect.

Automatic update of legend items to reflect the current state of the axes, specified as "on" or "off", or as numeric or logical 1 (true) or 0 (false). A value of "on" is equivalent to true, and "off" is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

If you delete an object from the axes, the legend updates to reflect the change regardless of whether this property is set to "on" or "off". (since R2022b)

Example: legend(["A","B"],"AutoUpdate","off")

Text for legend labels, specified as a cell array of character vectors, string array, or categorical array. To include special characters or Greek letters in the labels, use TeX markup. For a table of options, see the Interpreter property.

Legend title, returned as a legend text object. To add a legend title, set the String property of the legend text object. To change the title appearance, such as the font style or color, set legend text properties. For a list, see Text Properties.

plot(rand(3));
lgd = legend('line 1','line 2','line 3');
lgd.Title.String = 'My Legend Title';
lgd.Title.FontSize = 12;

Alternatively, use the title function to add a title and control the appearance.

plot(rand(3));
lgd = legend('line 1','line 2','line 3');
title(lgd,'My Legend Title','FontSize',12)

Text interpreter, specified as one of these values:

TeX Markup

By default, MATLAB supports a subset of TeX markup. Use TeX markup to add superscripts and subscripts, modify the font type and color, and include special characters in the text.

Modifiers remain in effect until the end of the text. Superscripts and subscripts are an exception because they modify only the next character or the characters within the curly braces. When you set the interpreter to "tex", the supported modifiers are as follows.

This table lists the supported special characters for the "tex" interpreter.

LaTeX Markup

To use LaTeX markup, set the interpreter to "latex". For inline mode, surround the markup with single dollar signs ($). For display mode, surround the markup with double dollar signs ($$).

"$\int_1^{20} x^2 dx$"

"$$\int_1^{20} x^2 dx$$"

The displayed text uses the default LaTeX font style. The FontName, FontWeight, and FontAngle properties do not have an effect. To change the font style, use LaTeX markup.

The maximum size of the text that you can use with the LaTeX interpreter is 1200 characters. For multiline text, this reduces by about 10 characters per line.

MATLAB supports most standard LaTeX math mode commands. For more information, see Supported LaTeX Commands. For examples that use TeX and LaTeX, see Greek Letters and Special Characters in Chart Text.

Font name, specified as a supported font name or "FixedWidth". To display and print text properly, you must choose a font that your system supports. The default font depends on your operating system and locale.

To use a fixed-width font that looks good in any locale, use "FixedWidth". The fixed-width font relies on the root FixedWidthFontName property. Setting the root FixedWidthFontName property causes an immediate update of the display to use the new font.

Font size, specified as a scalar value greater than zero in point units. The default font size depends on the specific operating system and locale.

If you change the axes font size, then MATLAB automatically sets the font size of the colorbar to 90% of the axes font size. If you manually set the font size of the colorbar, then changing the axes font size does not affect the colorbar font.

Character thickness, specified as 'normal' or 'bold'.

MATLAB uses the FontWeight property to select a font from those available on your system. Not all fonts have a bold weight. Therefore, specifying a bold font weight can still result in the normal font weight.

Character slant, specified as 'normal' or 'italic'.

Not all fonts have both font styles. Therefore, the italic font might look the same as the normal font.

Text color, specified as an RGB triplet, a hexadecimal color code, a color name, or a short name. The default color is black with a value of [0 0 0].

For a custom color, specify an RGB triplet or a hexadecimal color code.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

This table lists the default color palettes for plots in the light and dark themes.

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

Example: [0 0 1]

Example: 'blue'

Example: '#0000FF'

Background color, specified as an RGB triplet, a hexadecimal color code, a color name, or a short name. The default value of [1 1 1] corresponds to white.

For a custom color, specify an RGB triplet or a hexadecimal color code.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

This table lists the default color palettes for plots in the light and dark themes.

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

Example: legend({'A','B'},'Color','y')

Example: legend({'A','B'},'Color',[0.8 0.8 1])

Example: legend({'A','B'},'Color','#D9A2E9')

Box outline color, specified as an RGB triplet, a hexadecimal color code, a color name, or a short name. The default value of [0.15 0.15 0.15] corresponds to dark gray.

For a custom color, specify an RGB triplet or a hexadecimal color code.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

This table lists the default color palettes for plots in the light and dark themes.

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

Example: legend({'A','B'},'EdgeColor',[0 1 0])

Background transparency, specified as a scalar in the range [0, 1]. A value of 1 is fully opaque and 0 is completely transparent. Values between 0 and 1 are partially transparent. Here are some examples of legends with different BackgroundAlpha values.

Display of box outline, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Example: legend({'A','B'},'Box','off')

Width of box outline, specified as a positive value in point units. One point equals 1/72 inch.

Example: 1.5

State of visibility, specified as "on" or "off", or as numeric or logical 1 (true) or 0 (false). A value of "on" is equivalent to true, and "off" is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Context menu, specified as a ContextMenu object. Use this property to display a context menu when you right-click the object. Create the context menu using the uicontextmenu function.

Selection state, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Display of selection handles when selected, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Callback that executes when you click legend items, specified as one of these values:

If you specify this property using a function handle, then MATLAB passes the Legend object and an event data structure as the first and second input arguments to the function. This table describes the fields in the event data structure.

Example

You can create interactive legends so that when you click an item in the legend, the associated chart updates in some way. For example, you can toggle the visibility of the chart or change its line width. Set the ItemHitFcn property of the legend to a callback function that controls how the charts change. This example shows how to toggle the visibility of a chart when you click the chart icon or label in a legend. It creates a callback function that changes the Visible property of the chart to either 'on' or 'off'.

Copy the following code to a new function file and save it as hitcallback_ex1.m either in the current folder or in a folder on the MATLAB search path. The two input arguments, src and evnt, are the legend object and an event data structure. MATLAB automatically passes these inputs to the callback function when you click an item in the legend. Use the Peer field of the event data structure to access properties of the chart object associated with the clicked legend item.

function hitcallback_ex1(src,evnt)

if strcmp(evnt.Peer.Visible,'on')
    evnt.Peer.Visible = 'off';
else 
    evnt.Peer.Visible = 'on';
end

end

Then, plot four lines, create a legend, and assign the legend object to a variable. Set the ItemHitFcn property of the legend object to the callback function. Click items in the legend to show or hide the associated chart. The legend label changes to gray when you hide a chart.

plot(rand(4));
l = legend('Line 1','Line 2','Line 3','Line 4');
l.ItemHitFcn = @hitcallback_ex1;

Mouse-click callback, specified as one of these values:

Use this property to execute code when you click the object. If you specify this property using a function handle, then MATLAB passes two arguments to the callback function when executing the callback:

For more information on how to use function handles to define callback functions, see Create Callbacks for Graphics Objects.

Object creation function, specified as one of these values:

For more information about specifying a callback as a function handle, cell array, or character vector, see Create Callbacks for Graphics Objects.

This property specifies a callback function to execute when MATLAB creates the object. MATLAB initializes all property values before executing the CreateFcn callback. If you do not specify the CreateFcn property, then MATLAB executes a default creation function.

Setting the CreateFcn property on an existing component has no effect.

If you specify this property as a function handle or cell array, you can access the object that is being created using the first argument of the callback function. Otherwise, use the gcbo function to access the object.

Object deletion function, specified as one of these values:

For more information about specifying a callback as a function handle, cell array, or character vector, see Create Callbacks for Graphics Objects.

This property specifies a callback function to execute when MATLAB deletes the object. MATLAB executes the DeleteFcn callback before destroying the properties of the object. If you do not specify the DeleteFcn property, then MATLAB executes a default deletion function.

If you specify this property as a function handle or cell array, you can access the object that is being deleted using the first argument of the callback function. Otherwise, use the gcbo function to access the object.

Callback interruption, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

This property determines if a running callback can be interrupted. There are two callback states to consider:

Whenever MATLAB invokes a callback, that callback attempts to interrupt a running callback. The Interruptible property of the object owning the running callback determines if interruption is permitted. The Interruptible property has two possible values:

Callback queuing, specified as 'queue' or 'cancel'. The BusyAction property determines how MATLAB handles the execution of interrupting callbacks. There are two callback states to consider:

The BusyAction property determines callback queuing behavior only when both of these conditions are met:

Under these conditions, the BusyAction property of the object that owns the interrupting callback determines how MATLAB handles the interrupting callback. These are possible values of the BusyAction property:

Ability to capture mouse clicks, specified as one of these values:

Response to captured mouse clicks, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Deletion status, returned as an on/off logical value of type matlab.lang.OnOffSwitchState.

MATLAB sets the BeingDeleted property to 'on' when the DeleteFcn callback begins execution. The BeingDeleted property remains set to 'on' until the component object no longer exists.

Check the value of the BeingDeleted property to verify that the object is not about to be deleted before querying or modifying it.

Parent container, specified as a Figure object, Panel object, Tab object, or a TiledChartLayout object.

The Legend object must have the same parent as the associated axes. If you change the parent of the associated axes, then the Legend object automatically updates to use the same parent.

The object has no children. You cannot set this property.

Visibility of the object handle in the Children property of the parent, specified as one of these values:

If the object is not listed in the Children property of the parent, then functions that obtain object handles by searching the object hierarchy or querying handle properties cannot return it. Examples of such functions include the get, findobj, gca, gcf, gco, newplot, cla, clf, and close functions.

Hidden object handles are still valid. Set the root ShowHiddenHandles property to "on" to list all object handles regardless of their HandleVisibility property setting.

Type of graphics object, returned as 'legend'. Use this property to find all objects of a given type within a plotting hierarchy.

Object identifier, specified as a character vector or string scalar. You can specify a unique Tag value to serve as an identifier for an object. When you need access to the object elsewhere in your code, you can use the findobj function to search for the object based on the Tag value.

User data, specified as any MATLAB array. For example, you can specify a scalar, vector, matrix, cell array, character array, table, or structure. Use this property to store arbitrary data on an object.

If you are working in App Designer, create public or private properties in the app to share data instead of using the UserData property. For more information, see Share Data Within App Designer Apps.