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Python None comparison: should I use “is” or ==?
...n comparing arbitrary objects to singletons like None because it is faster and more predictable. is always compares by object identity, whereas what == will do depends on the exact type of the operands and even on their ordering.
This recommendation is supported by PEP 8, which explicitly states th...
Error “library not found for” after putting application in AdMob
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Sometimes you just remove the reference of the library and add reference again.
Apart from adding the Google Mobile Ads SDK and other libraries again from scratch, I would recommend you checking the Library Search Paths. There are instances when you copy or duplicate a target, ...
What are the differences between double-dot “..” and triple-dot “…” in Git diff commit ranges?
What are the differences between the following commands?:
5 Answers
5
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How to cast an Object to an int
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Beware, it can throw a ClassCastException if your object isn't an Integer and a NullPointerException if your object is null.
This way you assume that your Object is an Integer (the wrapped int) and you unbox it into an int.
int is a primitive so it can't be stored as an Object, the only way is to...
Android global variable
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You can extend the base android.app.Application class and add member variables like so:
public class MyApplication extends Application {
private String someVariable;
public String getSomeVariable() {
return someVariable;
}
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Creating an empty file in C#
...a difference is if the thread were aborted between the call to File.Create and the call to Dispose. If that race condition exists, I suspect it would also exist in the using version, if the thread were aborted at the very end of the File.Create method, just before the value was returned...
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What do helper and helper_method do?
... This is used for any method that you need to access from both controllers and helpers/views (standard helper methods are not available in controllers). e.g. common use case:
#application_controller.rb
def current_user
@current_user ||= User.find_by_id!(session[:user_id])
end
helper_method :curre...
Cluster analysis in R: determine the optimal number of clusters
..., calinski.best, "\n")
# 5 clusters!
Four. Determine the optimal model and number of clusters according to the Bayesian Information Criterion for expectation-maximization, initialized by hierarchical clustering for parameterized Gaussian mixture models
# See http://www.jstatsoft.org/v18/i06/pap...
How to move all files including hidden files into parent directory via *
... from one directory to another?. It shows solutions in Bash, zsh, ksh93, standard (POSIX) sh, etc.
You can use these two commands together:
mv /path/subfolder/* /path/ # your current approach
mv /path/subfolder/.* /path/ # this one for hidden files
Or all together (thanks pfnuesel):
mv /pa...
ASP.NET MVC - Set custom IIdentity or IPrincipal
...to extend the default so that I can call something like User.Identity.Id and User.Identity.Role . Nothing fancy, just some extra properties.
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