Re: Copy an Object (Again?)
KraftDiner [EMAIL PROTECTED] wrote: ... objs = myListOfObjects for obj in objs: if obj.flag: newObject = copy.deepcopy(obj) newObject.mirror() myListOfObjects.append(newObject) Never modify the very list you're looping on. I doubt this is the root of your problem, but, at any rate, loop on a COPY of the list you're modifying -- e.g. change the first statement to objs = list(myListOfObjects) Alex -- http://mail.python.org/mailman/listinfo/python-list
Copy an Object (Again?)
I'm having trouble getting a copy of and object... (a deep copy) I'm writing a method that creates a mirror image of an object (on screen) In order to do this i need to get a copy of the object and then modify some of its attributes. I tried: objs = myListOfObjects for obj in objs: if obj.flag: newObject = copy.deepcopy(obj) newObject.mirror() myListOfObjects.append(newObject) That doesn't seem to work.. the new object seems to disapear from existance. I'm wondering if its a bug in my application or if this is my shallow understanding of the language. TIA B. -- http://mail.python.org/mailman/listinfo/python-list
Re: Copy an Object (Again?)
KraftDiner wrote: I'm having trouble getting a copy of and object... (a deep copy) I'm writing a method that creates a mirror image of an object (on screen) In order to do this i need to get a copy of the object and then modify some of its attributes. I tried: objs = myListOfObjects for obj in objs: if obj.flag: newObject = copy.deepcopy(obj) newObject.mirror() myListOfObjects.append(newObject) That doesn't seem to work.. the new object seems to disapear from existance. I'm wondering if its a bug in my application or if this is my shallow understanding of the language. TIA B. I think you should provide more code, eg what attributes does your object have? imagine the situation like this import copy class A: ... lst=[1, 2, 3] ... a=A() b=copy.deepcopy(a) a __main__.A instance at 0x403e3c8c a.lst [1, 2, 3] b.lst [1, 2, 3] b.lst.append(4) b.lst [1, 2, 3, 4] a.lst [1, 2, 3, 4] or even if you could copy instances class X: def __init__(self, filename = /path/file) self.file = file(filename, w+) def modifyByteAt(offset): self.file.tell(offset) self.file.write(X) this is untested pseudocode, it should only give you an idea hth, Daniel ps: question to all what is a general approach to copy class instances? write own method or is there some __magic__ attribute or should one use pickle.dump? Regards, Daniel -- http://mail.python.org/mailman/listinfo/python-list
Re: Copy an Object (Again?)
KraftDiner wrote: I'm having trouble getting a copy of and object... (a deep copy) I'm writing a method that creates a mirror image of an object (on screen) In order to do this i need to get a copy of the object and then modify some of its attributes. I tried: objs = myListOfObjects for obj in objs: if obj.flag: newObject = copy.deepcopy(obj) newObject.mirror() myListOfObjects.append(newObject) That doesn't seem to work.. the new object seems to disapear from existance. I'm wondering if its a bug in my application or if this is my shallow understanding of the language. TIA B. Another remark, are you sure that your for obj in objs doesn't get you into an infinite loop? If myListOfObjects is a normal list, your assignment objs = myListofObjects doesn't make a copy of the list: MyListOfNumbers = [1,2,3,4] numbs = MyListOfNumbers MyListOfNumbers.append(5) numbs [1, 2, 3, 4, 5] If anything, that makes your alorithm hard to read, because you are iterating over a list while appending to it. -- http://mail.python.org/mailman/listinfo/python-list
Re: Copy an Object (Again?)
I was not very clear about it or even if you could copy instances class X: def __init__(self, filename = /path/file) self.file = file(filename, w+) def modifyByteAt(offset): self.file.tell(offset) self.file.write(X) this is untested pseudocode, it should only give you an idea even when x=X() and y=copyItSomehowFrom(x) what is supposed to be copied? the whole file? but where? in your case .. what is supposed to happen with the mirrored image? should it be mirrored inplace if I recall properly in import PIL.Image as image if you image.open an image and want to mirror it you can create a real copy and then save as it into a file my 2 cents -- http://mail.python.org/mailman/listinfo/python-list
