Check if gui is open matlab answers matlab central. You are assigning a handle to a field of a structure. Check existence of variable, script, function, folder, or class. The variable returned by the audioplayer function identifies the audio data and enables you to access object functions to play the audio. For chebwin, kaiser, and tukeywin, you must include a window parameter using the next syntax for more information on each window function and. Matlab how to check the existence of a handle stack. Or, for handles to local or nested functions, the function must be in the current file. I believe the answer to this question already exists several times online, but. Within a class delete method, isvalid always returns false you cannot override the isvalid method in handle subclasses. If you close the figure while waitfor is executing, an error occurs because the code attempts to access objects that no longer exist. You can save and load function handles in matlab, as you would any other variable. Can you please replace the line if legh handle to deleted axes to correctly. My goal is purely to prevent matlab from crashing when it encounters the expression existf in the code, where f is a function handle pointing to.
Now you want to test whether there is a valid handle in the field, and guard against everything that could be wrong. If you load a function handle, and the function file no longer exists on the path, the handle is invalid. Find all graphics objects matlab findall mathworks benelux. I tried ishandle,isvalid,isfield,isempty but they all dont work on a nonexistent field so i receive an error if i didnt declare the handle reference to non existent. Check if handle to axes exists at all r2017b matlab.
For example, the matlab audioplayer function creates a handle object that contains the audio source data to reproduce a specific sound segment. 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 example, if name exists in a restricted folder to which matlab does not have access, exist returns 0. Test for valid graphics or java object handle matlab. This matlab function returns a logical array in which each element is true if the corresponding element in h is a valid handle. Keep hold of the handle of the figure when you launch it.
Otherwise, matlab truncates the latter part of the name. Scope the function must be in scope at the time you create the handle. Check if handle to axes exists at all r2017b matlab answers. A handle variable becomes invalid if the object has been deleted. This matlab function returns true if the variant configuration data object exists for the model. For example, if name exists in a restricted folder to which matlab does not have access, exist returns 0 1 name is a variable in the workspace. Check if variant configuration data object exists for a. How to check the existence of a nonexistent handle matlab. Block execution and wait for condition matlab waitfor mathworks. I want to check if the specific handle or set of handles exist and then write necessary code whether to.633 782 1491 1035 1210 112 1091 965 1577 1379 615 1158 1576 1062 1357 1204 400 1497 257 1536 861 17 706 320 1444 388 319 219 705 614 260 1075 1112