Is it possible in matlab to load an object of which the class definition file was placed in separate package?
For example:
T = myTestClass;
save('T');
Now I want to place my class in a package, so I create the directory structure as follows:
+myTestPack/#myTestClass/myTestClass.m
Next I try to recover the saved object:
import myTestPack.*
load('T.mat');
The outcome is always:
Warning: Variable 'T' originally saved as a myTestClass cannot be instantiated as an object and will be read in as a uint32.
Is there any way to solve this problem? I would like to restructure my code but a lot of old data was saved as objects.
Maybe I need to add loadobj/saveobj methods to the definition file or maybe there is a way to rename the class from myTestClass to myTestPack.myTestClass?
Thank you for your suggestions!
You need to add loadobj method to your new class. You also need a simple class myTestClass in the old location with just a loadobj method which calls loadobj method of the moved class. MATLAB does not know that you have moved the class. When loading all it knows is that it is of class type myTestClass and tries to create one by looking up myTestClass.
Related
We have various class annotated with a scala macro annotation that add a method to that class. At compile time, We want to add a list of these annotated class in some other object . So that we can access that list at run time. Is there any way to achieve this?
I didn't find a straight way to do this but what I did was pretty simple. Whenever my macro finds my annotated class, It writes the name of the class to a file in resources. At runtime, I made that file content available as a list through a new class method.
I've implemented a handle class in MATLAB, and I've tried to copy an object of the class by calling the following two functions:
objByteArray = getByteStreamFromArray(obj);
newObj = getArrayFromByteStream(objByteArray);
But from time to time I get the following error:
Error using getArrayFromByteStream
Unable to read data stream because the data contains a bad version or endian-key
Is there another way to copy an object of a handle class?
Since you're working with a handle class, you can inherit your class from matlab.mixin.Copyable, which will give your class a customizable copy method.
By default, the copy method will implement a shallow copy of the class properties (i.e. if the class properties are themselves handle classes, the copies will be references to the original properties), but you can customize the copy operation to implement a deep copy (i.e. a copy operation is performed on the class properties as well).
Documentation for matlab.mixin.Copyable.
Is it possible to write ObjectScript method, which will create new class in namespace and compile it? I mean programmatically create new class and store it. If so, can I edit this class using ObjectScript later(and recompile)?
Reason: I have class structure defined in string variable and I need to add new class to namespace according this string.
Nothing is impossible. Everything in Caché can be created programmatically. And, Classes is not a execution. There are at least two ways to do it:
simple SQL Query CREATE TABLE, will create a class.
and as you already mentioned ObjectScript Code, which can do this.
All of definition of any classes defined in other classes. Which you can find in package %Dictionary.
The class itself defined in %Dictionary.ClassDefinition. Which have some properties, for defining any parts of classes. So, this is a simple code which create some class, with one property.
set clsDef=##class(%Dictionary.ClassDefinition).%New()
set clsDef.Name="package.classname"
set clsDef.Super="%Persistent"
set propDef=##class(%Dictionary.PropertyDefinition).%New()
set propDef.Name="SomeProperty"
set propDef.Type="%String"
do clsDef.Properties.Insert(propDef)
do clsDef.%Save()
And in latest versions, there is one more way for create/change class. If you have text of class as you can see it in Studio. Then, you can load it in Caché, with class %Compiler.UDL.TextServices
Yes, it is. You likely want to make use of %Dictionary.ClassDefinition and the related %Dictionary.*Definition classes (especially %Dictionary.PropertyDefinition, %Dictionary.MethodDefinition and %Dictionary.IndexDefinition) to create and/or modify your class. Provided your string contains some reasonable representation of the data, you should be able to create the class this way.
The actual class documentation is available at http://docs.intersystems.com/cache20141/csp/documatic/%25CSP.Documatic.cls?CLASSNAME=%25Dictionary.ClassDefinition
You can then compile the class by calling $system.OBJ.Compile("YourPackage.YourClass","ck").
(Note: If your string contains the exported XML definition of the class, you could also write the XML representation to a stream and then call $system.OBJ.LoadStream() to import the XML definition. I would only recommend this if you have an exported class definition to start with.)
I defined a class and created the object Obj. Now I want to save Obj along with other variables to a certain folder:
filename = 'C:\Users\username\Desktop\foldername\file.mat' ;
save(filename,'Obj','var1','var2')
The normal and intuitive thing to do next is loading file.mat for further work:
load (file.mat)
Unfortunately Obj loses its structur and is not constructed as an object of my class but as matrix of uint32. There is a thread to this problem at mathworks.com:
https://www.mathworks.com/matlabcentral/newsreader/view_thread/261903 but it is not helping me. All functions and classdef files and matfiles etc are in the same path.
thx for helping.
So far this one seems to go against the grain of Php OOP. Let me explain further with an example.
class main has a function called get($name), what I would like get to do is based on the value of $name, (e.g. 'path/file') would find the corresponding file and include it, so the class in path/file can be used.
My goal with this and the reason I want to do this, is when I call $main->get('path/file'), I'd like an object returned of the class within the file, so far the only solution I can figure out is to use
include($main->get('path/file'));
And within said file would be an object defined outside the class body within path/file.php, but that doesn't really solve the issue as it limits me to using the object defined in that file, and I can only use this include call outside a class body. Does anyone have any ideas on how this can be approached?