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How to get rid of the 'undeclared selector' warning
I want to use a selector on an NSObject instance without the need for an implemented protocol. For example, there's a category method that should set an error property if the NSObject instance it's called on supports it. This is the code, and the code works as intended:
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How do I use su to execute the rest of the bash script as that user?
I've written a script that takes, as an argument, a string that is a concatenation of a username and a project. The script is supposed to switch (su) to the username, cd to a specific directory based upon the project string.
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What is the difference between a generative and a discriminative algorithm?
...erstand the difference between a generative and a
discriminative algorithm, keeping in mind that I am just a beginner.
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What are the differences between the threading and multiprocessing modules?
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What Giulio Franco says is true for multithreading vs. multiprocessing in general.
However, Python* has an added issue: There's a Global Interpreter Lock that prevents two threads in the same process from running Python code at the same time. This means that if yo...
Calling a function when ng-repeat has finished
...ally a "on ng repeat finished rendering" handler. I am able to detect when it is done but I can't figure out how to trigger a function from it.
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DynamoDB vs MongoDB NoSQL [closed]
I'm trying to figure it out what can I use for a future project, we plan to store from about 500k records per month in the first year and maybe more for the next years this is a vertical application so there's no need to use a database for this, that's the reason why I decided to choose a noSQL data...
Immutable vs Unmodifiable collection
...ther code may still have access to. So while you can't make any changes to it if you only have a reference to the unmodifiable collection, you can't rely on the contents not changing.
An immutable collection guarantees that nothing can change the collection any more. If it wraps a modifiable collec...
What is better, adjacency lists or adjacency matrices for graph problems in C++?
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It depends on the problem.
Adjacency Matrix
Uses O(n^2) memory
It is fast to lookup and check for presence or absence of a specific edge
between any two nodes O(1)
It is slow to iterate over all edges
It is slow to add/...
When do we have to use copy constructors?
...iler creates a copy constructor for a class. In which case do we have to write a user-defined copy constructor? Can you give some examples?
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Python exit commands - why so many and when should each be used?
It seems that python supports many different commands to stop script execution. The choices I've found are: quit() , exit() , sys.exit() , os._exit()
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