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Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...
Simple insecure two-way data “obfuscation”?
...e to figure out your keys by just assuming that you used this code as-is! All you have to do is change some of the numbers (must be <= 255) in the Key and Vector arrays (I left one invalid value in the Vector array to make sure you do this...). You can use https://www.random.org/bytes/ to gener...
TypeError: 'NoneType' object is not iterable in Python
... Correct, But the common scenario author intended here is totally to skip the for loop instead of raising an exception. Python's design is flawed here. When None is treated as an iterable it must return empty list at least. This exception never helped anyone in real life other than m...
logger configuration to log to file and print to stdout
...d the StreamHandler. The StreamHandler writes to stderr. Not sure if you really need stdout over stderr, but this is what I use when I setup the Python logger and I also add the FileHandler as well. Then all my logs go to both places (which is what it sounds like you want).
import logging
logging.g...
Xcode 5.1 - No architectures to compile for (ONLY_ACTIVE_ARCH=YES, active arch=x86_64, VALID_ARCHS=i
...from the workspace in the left pane of Xcode and close Xcode.
Run "pod install" from the command line to recreate the "Pods" project.
Re-open Xcode and make sure "Build Active Architecture Only" is set to "No" in the build settings of both the "Pods" project and your own project.
Clean and build.
...
Accept function as parameter in PHP
... to find some documentation to link to first, and didn't know what it was called exactly. Ah well, now I'll know for when I need to do this as well. Thanks.
– Rob
Apr 23 '10 at 17:01
...
What is the difference between C# and .NET?
.... The C# specification says only a very little about the environment (basically, that it should contain some types such as int, but that's more or less all).
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Extending the User model with custom fields in Django
...ing the fields for additional information. This one-to-one model is often called a profile model, as it might store non-auth related information about a site user.
That said, extending django.contrib.auth.models.User and supplanting it also works...
Substituting a custom User model
Some kinds of p...
Bad class file magic or version
...K section, when you add an Android SDK you should provide the Java SDK and all my Android SDKs uses Java 8 as SDK so it create the class files with the wrong version even if the Project level is 1.7 (i don't know why, i supposed that everything was choosed by Project level).
Now i changed the SDK (...