
Martin Wiechert wrote:
Thanks Travis.
Do I understand correctly that the only way to be really safe is to make a copy and not to export a reference to it? Because anybody having a reference to the owner of the data can override the flag?
No, that's not quite correct. Of course in C, anybody can do anything they want to the flags. In Python, only the owner of the object itself can change the writeable flag once it is set to False. So, if you only return a "view" of the array (a.view()) then the Python user will not be able to change the flags. Example: a = array([1,2,3]) a.flags.writeable = False b = a.view() b.flags.writeable = True # raises an error. c = a c.flags.writeable = True # can be done because c is a direct alias to a. Hopefully, that explains the situation a bit better. -Travis