15.2.10 Interacting with Plots

The user can select points on a plot with the ginput function or selection the position at which to place text on the plot with the gtext function using the mouse. Menus may also be created and populated with specific user commands via the uimenu function.

Function File: [x, y, buttons] = ginput (n)

Function File: [x, y, buttons] = ginput ()

Return the position and type of mouse button clicks and/or key strokes in the current figure window.

If n is defined, then capture n events before returning. When n is not defined ginput will loop until the return key RET is pressed.

The return values x, y are the coordinates where the mouse was clicked in the units of the current axes. The return value button is 1, 2, or 3 for the left, middle, or right button. If a key is pressed the ASCII value is returned in button.

Implementation Note: ginput is intenteded for 2-D plots. For 3-D plots see the currentpoint property of the current axes which can be transformed with knowledge of the current view into data units.

See also: gtext, waitforbuttonpress.

Function File: waitforbuttonpress ()

Function File: b = waitforbuttonpress ()

Wait for mouse click or key press over the current figure window.

The return value of b is 0 if a mouse button was pressed or 1 if a key was pressed.

See also: waitfor, ginput, kbhit.

Function File: gtext (s)

Function File: gtext ({s1, s2, …})

Function File: gtext ({s1; s2; …})

Function File: gtext (…, prop, val, …)

Function File: h = gtext (…)

Place text on the current figure using the mouse.

The text is defined by the string s. If s is a cell string organized as a row vector then each string of the cell array is written to a separate line. If s is organized as a column vector then one string element of the cell array is placed for every mouse click.

Optional property/value pairs are passed directly to the underlying text objects.

The optional return value h is a graphics handle to the created text object(s).

See also: ginput, text.

Function File: hui = uimenu (property, value, …)

Function File: hui = uimenu (h, property, value, …)

Create a uimenu object and return a handle to it.

If h is omitted then a top-level menu for the current figure is created. If h is given then a submenu relative to h is created.

uimenu objects have the following specific properties:

"accelerator"

A string containing the key combination together with CTRL to execute this menu entry (e.g., "x" for CTRL+x).

"callback"

Is the function called when this menu entry is executed. It can be either a function string (e.g., "myfun"), a function handle (e.g., @myfun) or a cell array containing the function handle and arguments for the callback function (e.g., {@myfun, arg1, arg2}).

"checked"

Can be set "on" or "off". Sets a mark at this menu entry.

"enable"

Can be set "on" or "off". If disabled the menu entry cannot be selected and it is grayed out.

"foregroundcolor"

A color value setting the text color for this menu entry.

"label"

A string containing the label for this menu entry. A "&"-symbol can be used to mark the "accelerator" character (e.g., "E&xit")

"position"

An scalar value containing the relative menu position. The entry with the lowest value is at the first position starting from left or top.

"separator"

Can be set "on" or "off". If enabled it draws a separator line above the current position. It is ignored for top level entries.

Examples:

f = uimenu ("label", "&File", "accelerator", "f");
e = uimenu ("label", "&Edit", "accelerator", "e");
uimenu (f, "label", "Close", "accelerator", "q", ...
           "callback", "close (gcf)");
uimenu (e, "label", "Toggle &Grid", "accelerator", "g", ...
           "callback", "grid (gca)");

See also: figure.