Find handle objects - MATLAB - MathWorks France (2024)

FAQs

How do you get the handle of an object in MATLAB? ›

h = gco returns the handle of the current object. h = gco(figure_handle) returns the handle of the current object in the figure specified by figure_handle .

Use isgraphics to determine if a variable is a valid graphics object handle. A handle variable ( h in this case) can still exist, but not be a valid handle if the object to which it refers has been deleted. For more information on deleted handles, see Deleted Handle Objects.

h = findall( objhandles , prop 1, value 1,..., prop N, value N) returns the handles of all objects in the hierarchy that have the specified properties set to the specified values. For example, h = findall(gcf,'Type','text','Color','r') returns all text objects in the current figure that have a red color.

Equality of Handle Objects

You can use == and isequal to test for two different relationships among handle objects: The handles refer to the same object: == and isequal return true . The handles refer to objects of the same class that have the same values, but are not the same objects — only isequal returns true .

Use the gcf command to get the current figure handle. surf(peaks) fig = gcf; % current figure handle fig.

Handle objects enable more than one variable to refer to the same object. Handle-object behavior affects what happens when you copy handle objects and when you pass them to functions.

What Is a Function Handle? A function handle is a MATLAB^® data type that stores an association to a function. Indirectly calling a function enables you to invoke the function regardless of where you call it from.

B = isvalid( H ) returns a logical array in which each element is true if the corresponding element in H is a valid handle. A handle variable becomes invalid if the object has been deleted. Within a class delete method, isvalid always returns false . You cannot override the isvalid method in handle subclasses.

Value objects are associated with a specific variable. Handle objects can be referenced by multiple variables. Whether you implement a handle or value class depends on what your class represents and how you want objects to behave. MATLAB^® handle variables support reference semantics.

Get the handle when you initially display the image in a figure window using the imshow syntax that returns a handle. Get the handle after you have displayed the image in a figure window using the imhandles function. You must specify a handle to the figure window as a parameter.

How do you find all objects of a class in MATLAB? ›

Hmatch = findobj( H ,'-class', class ) finds all objects belonging to the specified class. Hmatch = findobj( H ,'-isa', class ) finds all objects belonging to the specified class.

A function handle is a MATLAB^® data type that represents a function. A typical use of function handles is to pass a function to another function. For example, you can use function handles as input arguments to functions that evaluate mathematical expressions over a range of values.

Description: Use the equal sign to assign values to a variable. The syntax B = A stores the elements of A in variable B . The = character is for assignment, whereas the == character is for comparing the elements in two arrays.

When comparing two handle objects, use == to test whether objects have the same handle. Use isequal to determine if two objects with different handles have equal property values. When comparing empty object arrays, isequal returns logical 1 ( true ) only when the arrays have the same size and class.

TF = isscalar( A ) returns logical 1 ( true ) if A is a scalar. Otherwise, it returns logical 0 ( false ). A scalar is a two-dimensional array that has a size of 1-by-1.

It is the second highest level object you can create. To create a figure, use the figure function like so: >> fhandle = figure; This creates a new figure window and stores all the figure data in the variable fhandle.

ht = matlabFunction( f ) converts the symbolic expression or function f to a MATLAB^® function with handle ht . If there is an equivalent MATLAB function operating on the double data type for the symbolic expression or function, then the converted function can be used without Symbolic Math Toolbox™.

Find Handle Object Properties

The findprop method returns the matlab. metadata. Property object for the specified object and property. The property can also be a dynamic property created by the addprop method of the dynamicprops class.