@jonB Hi. I totally agree with what you say. But part of it doesn't work. That part is when I run a script that defines a class and then immediately go to the console and try to use the class. This used to work and has stopped. I could even import other modules in the same directory as the first I ran, but now that doesn't work anymore.
I copied your test script and put it in a file, which I then ran. Here is the result:
3.5.1 (default, Sep 20 2016, 14:05:14)
[GCC 4.2.1 Compatible Apple LLVM 7.3.0 (clang-703.0.31)]
cwd: /private/var/mobile/Containers/Shared/AppGroup/87C36EF0-5007-410A-81F1-2CDA5EF1C05E/Pythonista3/Documents
sys.path:
['/private/var/mobile/Containers/Shared/AppGroup/87C36EF0-5007-410A-81F1-2CDA5EF1C05E/Pythonista3/Documents', '/private/var/mobile/Containers/Shared/AppGroup/87C36EF0-5007-410A-81F1-2CDA5EF1C05E/Pythonista3/Documents/site-packages-3', '/private/var/mobile/Containers/Shared/AppGroup/87C36EF0-5007-410A-81F1-2CDA5EF1C05E/Pythonista3/Documents/site-packages', '/var/containers/Bundle/Application/AAFBB031-7AB0-4862-8A10-4DE7B07D7E10/Pythonista3.app/Frameworks/Py3Kit.framework/pylib', '/var/containers/Bundle/Application/AAFBB031-7AB0-4862-8A10-4DE7B07D7E10/Pythonista3.app/Frameworks/Py3Kit.framework/pylib/site-packages', '/var/containers/Bundle/Application/AAFBB031-7AB0-4862-8A10-4DE7B07D7E10/Pythonista3.app/Frameworks/Py3Kit.framework/pylib/site-packages/PIL_compat']
i am a global
When I then print(x) on the console it works as per your example.
Now for the weird part! I retried my running my class definition. It didn't work. I did it again. It didn't work. Out of desperation I tried import my class--and it worked! I then went a=myclass.myclass(0.,0.) and it works. Just like it used to.