Search Results

Search found 13815 results on 553 pages for 'gae python'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 174/553 | < Previous Page | 170 171 172 173 174 175 176 177 178 179 180 181  | Next Page >

  • Python: why can't descriptors be instance variables?

    - by Continuation
    Say I define this descriptor: class MyDescriptor(object): def __get__(self, instance, owner): return self._value def __set__(self, instance, value): self._value = value def __delete__(self, instance): del(self._value) And I use it in this: class MyClass1(object): value = MyDescriptor() >>> m1 = MyClass1() >>> m1.value = 1 >>> m2 = MyClass1() >>> m2.value = 2 >>> m1.value 2 So value is a class attribute and is shared by all instances. Now if I define this: class MyClass2(object) value = 1 >>> y1 = MyClass2() >>> y1.value=1 >>> y2 = MyClass2() >>> y2.value=2 >>> y1.value 1 In this case value is an instance attribute and is not shared by the instances. Why is it that when value is a descriptor it can only be a class attribute, but when value is a simple integer it becomes an instance attribute?

    Read the article

  • Appending item to lists - python

    - by ariel
    I have a list lets say a=[[1,2],[3,4],[5,6]]. I want to add to each item in a the char 'a'. when I use a=[x.append('a') for x in a] it return [None,None,None]. But if I use a1=[x.append('a') for x in a] then it do someting odd. a and not a1 is [[1,2,a],[3,4,a],[5,6,a]]. I don't understand why the first return [None, None, None] nor why the second works on a.

    Read the article

  • Python: Behavior of object in set operations

    - by Josh Arenberg
    I'm trying to create a custom object that behaves properly in set operations. I've generally got it working, but I want to make sure I fully understand the implications. In particular, I'm interested in the behavior when there is additional data in the object that is not included in the equal / hash methods. It seems that in the 'intersection' operation, it returns the set of objects that are being compared to, where the 'union' operations returns the set of objects that are being compared. To illustrate: class MyObject: def __init__(self,value,meta): self.value = value self.meta = meta def __eq__(self,other): if self.value == other.value: return True else: return False def __hash__(self): return hash(self.value) a = MyObject('1','left') b = MyObject('1','right') c = MyObject('2','left') d = MyObject('2','right') e = MyObject('3','left') print a == b # True print a == c # False for i in set([a,c,e]).intersection(set([b,d])): print "%s %s" % (i.value,i.meta) #returns: #1 right #2 right for i in set([a,c,e]).union(set([b,d])): print "%s %s" % (i.value,i.meta) #returns: #1 left #3 left #2 left Is this behavior documented somewhere and deterministic? If so, what is the governing principle?

    Read the article

  • Multiple levels of 'collection.defaultdict' in Python

    - by Morlock
    Thanks to some great folks on SO, I discovered the possibilities offered by collections.defaultdict, notably in readability and speed. I have put them to use with success. Now I would like to implement three levels of dictionaries, the two top ones being defaultdict and the lowest one being int. I don't find the appropriate way to do this. Here is my attempt: from collections import defaultdict d = defaultdict(defaultdict) a = [("key1", {"a1":22, "a2":33}), ("key2", {"a1":32, "a2":55}), ("key3", {"a1":43, "a2":44})] for i in a: d[i[0]] = i[1] Now this works, but the following, which is the desired behavior, doesn't: d["key4"]["a1"] + 1 I suspect that I should have declared somewhere that the second level defaultdict is of type int, but I didn't find where or how to do so. The reason I am using defaultdict in the first place is to avoid having to initialize the dictionary for each new key. Any more elegant suggestion? Thanks pythoneers!

    Read the article

  • Best way to design a class in python

    - by Fraz
    So, this is more like a philosophical question for someone who is trying to understand classes. Most of time, how i use class is actually a very bad way to use it. I think of a lot of functions and after a time just indent the code and makes it a class and replacing few stuff with self.variable if a variable is repeated a lot. (I know its bad practise) But anyways... What i am asking is: class FooBar: def __init__(self,foo,bar): self._foo = foo self._bar = bar self.ans = self.__execute() def __execute(self): return something(self._foo, self._bar) Now there are many ways to do this: class FooBar: def __init__(self,foo): self._foo = foo def execute(self,bar): return something(self._foo, bar) Can you suggest which one is bad and which one is worse? or any other way to do this. This is just a toy example (offcourse). I mean, there is no need to have a class here if there is one function.. but lets say in __execute something() calls a whole set of other methods.. ?? Thanks

    Read the article

  • Manipulating Directory Paths in Python

    - by G Ullman
    Basically I've got this current url and this other key that I want to merge into a new url, but there are three different cases. Suppose the current url is localhost:32401/A/B/foo if key is bar then I want to return localhost:32401/A/B/bar if key starts with a slash and is /A/bar then I want to return localhost:32401/A/bar finally if key is its own independent url then I just want to return that key = htt p://foo.com/bar - http://foo.com/bar I assume there is a way to do at least the first two cases without manipulating the strings manually, but nothing jumped out at me immediately in the os.path module.

    Read the article

  • Python script not working when run from browser directly

    - by splatterdash
    I'm trying to run this script: import re, os def build_pool(cwd): global xtn_pool, file_pool xtn, xtn_pool = re.compile('\\.[0-9a-zA-Z]{1,4}$'), [] file_pool = [files for files in os.listdir(cwd) if os.path.isfile(files) and xtn.search(files)] # Lists all the file extension in the folder for file in file_pool: if not xtn_pool.__contains__(xtn.search(file).group()): xtn_pool.append(xtn.search(file).group()) return xtn_pool.sort(), file_pool if __name__ == '__main__': import sys #if path is given, change working directory to path if len(sys.argv) >= 2: os.chdir(sys.argv[1]) build_pool(os.getcwd()) #if no path is given when running, do renaming in current folder else: build_pool(os.getcwd()) print('The folder contains the following extensions: ') for i in range(0, len(xtn_pool)): print(repr(i+1) + '. ' + xtn_pool[i][1:]) opt = int(input('Which one would you like to replace? ')) xtn_pick = xtn_pool[opt-1] # Lists all the file with the chosen extension xtn_file_pool = [file for file in file_pool if file.endswith(xtn_pick)] print('There are {0} files with the {1} extension.'.format(len(xtn_file_pool), xtn_pick)) xtn_new = input('Input replacement extension: ') # The actual renaming process for file in xtn_file_pool: os.rename(file, file[:-len(xtn_pick)+1] + xtn_new) directly from my file browser (Nautilus), but for some reason it's not working. When I run it from terminal (python3 scriptname.py) it works fine as intended. But when I just click the script file in Nautilus, choose 'Run in Terminal', it always stops after asking 'Input replacement extension: '. How can I make this script run without using the terminal?

    Read the article

  • Python/Django: log to console under runserver, log to file under Apache

    - by Justin Grant
    How can I send trace messages to the console (like print) when I'm running my Django app under manage.py runserver, but have those messages sent to a log file when I'm running the app under Apache? I reviewed Django logging and although I was impressed with its flexibility and configurability for advanced uses, I'm still stumped with how to handle my simple use-case. My apologies for not being able to find the answer elsewhere-- this is a newbie question I know.

    Read the article

  • Python built-in id() not consistent:

    - by Dannellyz
    Hoping someone can explain the following discrepancy: >>> s1 = "Cyber security" >>> s2 = "Cyber security" >>> id(s1) == id(s1) True >>> id(s1) == id(s2) False >>> s1 = "cyber" >>> s2 = "cyber" >>> id(s1) == id(s2) True >>> s2 = "cyber " >>> s2 = "cyber " >>> id(s1) == id(s2) False Why does the space make the id() False, yet different variables with no spaces are True?

    Read the article

  • python and overflowing byte?

    - by Meloun
    Hi all, I need to make a variable with similar behaviour like in C lanquage. I need byte or unsigned char with range 0-255. This variable should overflow, that means... myVar = 255 myVar += 1 print myVar #!!myVar = 0!!

    Read the article

  • Replace special characters in python

    - by Marcos Placona
    Hi, I have some text coming from the web as such: £6.49 Obviously I would like this to be displayed as: £6.49 I have tried the following so far: s = url['title'] s = s.encode('utf8') s = s.replace(u'Â','') And a few variants on this (after finding it on this very same forum) But still no luck as I keep getting: UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 100: ordinal not in range(128) Could anyone help me getting this right? UPDATE: Adding the reppr examples and content type u'Star Trek XI &#xA3;3.99' u'Oscar Winners Best Pictures Box Set \xc2\xa36.49' Content-Type: text/html; charset=utf-8 Thanks in advance

    Read the article

  • Python: How should I make instance variables available?

    - by swisstony
    Suppose I have: class myclass: def __init__(self): self.foo = "bar" where the value of foo needs to be available to users of myclass. Is it OK to just read the value of foo directly from an instance of myclass? Should I add a get_foo method to myclass or perhaps add a foo property? What's the best practice here?

    Read the article

  • python: importing modules with incorrect import statements => unexhaustive info from resulting Impor

    - by bbb
    Hi there, I have a funny problem I'd like to ask you guys ('n gals) about. I'm importing some module A that is importing some non-existent module B. Of course this will result in an ImportError. This is what A.py looks like import B Now let's import A >>> import A Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/tmp/importtest/A.py", line 1, in <module> import B ImportError: No module named B Alright, on to the problem. How can I know if this ImportError results from importing A or from some corrupt import inside A without looking at the error's string representation. The difference is that either A is not there or does have incorrect import statements. Hope you can help me out... Cheers bb

    Read the article

  • Testing variable types in Python

    - by Jasper
    Hello, I'm creating an initialising function for the class 'Room', and found that the program wouldn't accept the tests I was doing on the input variables. Why is this? def __init__(self, code, name, type, size, description, objects, exits): self.code = code self.name = name self.type = type self.size = size self.description = description self.objects = objects self.exits = exits #Check for input errors: if type(self.code) != type(str()): print 'Error found in module rooms.py!' print 'Error number: 110' elif type(self.name) != type(str()): print 'Error found in module rooms.py!' print 'Error number: 111' elif type(self.type) != type(str()): print 'Error found in module rooms.py!' print 'Error number: 112' elif type(self.size) != type(int()): print 'Error found in module rooms.py!' print 'Error number: 113' elif type(self.description) != type(str()): print 'Error found in module rooms.py!' print 'Error number: 114' elif type(self.objects) != type(list()): print 'Error found in module rooms.py!' print 'Error number: 115' elif type(self.exits) != type(tuple()): print 'Error found in module rooms.py!' print 'Error number: 116' When I run this I get this error: Traceback (most recent call last): File "/Users/Jasper/Development/Programming/MyProjects/Game Making Challenge/Europa I/rooms.py", line 148, in <module> myRoom = Room(101, 'myRoom', 'Basic Room', 5, '<insert description>', myObjects, myExits) File "/Users/Jasper/Development/Programming/MyProjects/Game Making Challenge/Europa I/rooms.py", line 29, in __init__ if type(self.code) != type(str()): TypeError: 'str' object is not callable

    Read the article

  • Importing data from a text file using python

    - by Will
    I have a text file containing data in rows and columns (~17000 rows in total). Each column is a uniform number of characters long, with the 'unused' characters filled in by spaces. For example, the first column is 11 characters long, but the last four characters in that column are always spaces (so that it appears to be a nice column when viewed with a text editor). Sometimes it's more than four if the entry is less than 7 characters. The columns are not otherwise separated by commas, tabs, or spaces. They are also not all the same number of characters (the first two are 11, the next two are 8 and the last one is 5 - but again, some are spaces). What I want to do is import the entires (which are numbers) in the last two columns if the second column contains the string 'OW' somewhere in it. Any help would be greatly appreciated.

    Read the article

  • Serialize the @property methods in a Python class.

    - by ashchristopher
    Is there a way to have any @property definitions passed through to a json serializer when serializing a Django model class? example: class FooBar(object.Model) name = models.CharField(...) @property def foo(self): return "My name is %s" %self.name Want to serialize to: [{ 'name' : 'Test User', 'foo' : 'My name is Test User', },]

    Read the article

  • change values in a list - python

    - by ariel
    I have this code: a=[['a','b','c'],['a','f','c'],['a','c','d']] for x in a: for y in x: if 'a' in x: x.replace('a','*')` but the result is: a=[['a','b','c'],['a','f','c'],['a','c','d']] and bot a=[['b','c'],['f','c'],['c','d']] What should I do so the changes will last?

    Read the article

  • python convert 12 bit image encoded in a string to 8 bit png

    - by ks
    I have a string that is read from a usb apogee camera that is a 12-bit grayscale image with the 12-bits each occupying the lowest 12 bits of 16-bits words. I want to create a 8-bit png from this string by ignoring the lowest 4 bits. I can convert it to a 16-bit image where the highest 4 bits are always zero using PIL with import Image imageStr is the image string imageSize is the image size img=Image.fromstring("I", imageSize, imageStr, "raw", "I;16", 0,1) img.save("MyImage.png", "PNG") Anyway I can do something similar to create a 8-bit image without completely unpacking the string doing arithmetic and making a new string?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 170 171 172 173 174 175 176 177 178 179 180 181  | Next Page >