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.

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.

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.

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.

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.

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.

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.

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.

How do you check handle equality in MATLAB? ›

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 .

Description. k = find( X ) returns a vector containing the linear indices of each nonzero element in array X . If X is a vector, then find returns a vector with the same orientation as X . If X is a multidimensional array, then find returns a column vector of the linear indices of the result.

The instanceof operator allows to check whether an object belongs to a certain class. It also takes inheritance into account. Such a check may be necessary in many cases. For example, it can be used for building a polymorphic function, the one that treats arguments differently depending on their type.

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™.

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.