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Does every Core Data Relationship have to have an Inverse?
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An inverse relationship doesn't just
make things more tidy, it's actually
used by Core Data to maintain data
integrity.
-- Cocoa Dev Central
You should typically model
relationships in both directions, and
specify the inverse relationships
appropriately. Core Data uses this
i...
What is the difference between a regular string and a verbatim string?
... = @"C:\myfolder\myfile.txt";
The @ symbol means to read that string literally, and don't interpret control characters otherwise.
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Cost of len() function
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Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
d3 axis labeling
...eet to style these labels as you like, either together (.label) or individually (.x.label, .y.label).
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Embedding Python in an iPhone app
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It doesn't really matter how you build Python -- you don't need to build it in Xcode, for example -- but what does matter is the product of that build.
Namely, you are going to need to build something like libPython.a that can be statica...
How to check if std::map contains a key without doing insert?
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Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.
Alternately my_map.find( key ) != my_map.end() works too.
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How to make a HTML Page in A4 paper size page(s)?
...e the margins as you want them to be. */
}
}
In case you think you really need pixels (you should actually avoid using pixels), you will have to take care of choosing the correct DPI for printing:
72 dpi (web) = 595 X 842 pixels
300 dpi (print) = 2480 X 3508 pixels
600 dpi (high quality prin...
how to File.listFiles in alphabetical order?
... File is a comparable class, which by default sorts pathnames lexicographically. If you want to sort them differently, you can define your own comparator.
If you prefer using Streams:
A more modern approach is the following. To print the names of all files in a given directory, in alphabetical or...
Why {} + {} is NaN only on the client side? Why not in Node.js?
...le._commandLineAPI = new CommandLineAPI(this._commandLineAPIImpl, isEvalOnCallFrame ? object : null);
expression = "with ((window && window.console && window.console._commandLineAPI) || {}) {\n" + expression + "\n}";
}
var result = evalFunction.call(object, expression...
What is the fastest way to get the value of π?
I'm looking for the fastest way to obtain the value of π, as a personal challenge. More specifically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in.
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