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How to extract numbers from a string in Python?
I would extract all the numbers contained in a string. Which is the better suited for the purpose, regular expressions or the isdigit() method?
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What is the difference between JOIN and UNION?
...ed when columns from one table match columns from another. This match is called the join condition.
This makes joins really great for looking up values and including them in results. This is usually the result of denormalizing (reversing normalization) and involves using the foreign key in one ta...
Linux vi arrow keys broken in insert mode
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@pts - only on broken systems. Starting vim as vi on all of my boxes works just fine; however, there are some CentOS boxes I have used that demonstrate the behavior you are talking about.
– Chas. Owens
May 1 '09 at 22:22
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OAuth secrets in mobile apps
...ssue with the OAuth design that we are facing ourselves. We opted to proxy all calls through our own server. OAuth wasn't entirely flushed out in respect of desktop apps. There is no prefect solution to the issue that I've found without changing OAuth.
If you think about it and ask the question wh...
Why should I use tags vs. release/beta branches for versioning?
... to use to work with tags, but what I'd like to know is why use tagging at all if I can just create a new branch called 1.1.0 and not have to cloud my mind with a whole new set of git commands?
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Abandoning changes without deleting from history
...rst time you push this closed head to another repository since you are actually create additional heads in the remote repository when you push. So tell Mercurial that this is okay with --force. People who pull the closed head wont be bothered by any warnings.
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Speed up the loop operation in R
...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(te...
How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
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Access parent DataContext from DataTemplate
... this exact code in my project but it's leaking ViewModels (Finalizer not called, Command binding seems to retain DataContext). Can you verify that this issue exists for you as well?
– Joris Weimar
Jan 22 '13 at 11:05
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Difference between a virtual function and a pure virtual function [duplicate]
... class. Derived classes can override virtual functions. Virtual functions called through base class pointers/references will be resolved at run-time. That is, the dynamic type of the object is used instead of its static type:
Derived d;
Base& rb = d;
// if Base::f() is virtual and Derived o...