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How to count certain elements in array?
...t later will have to spend some time to check what it does, and lose focus from their task. An abstraction is far superior: const count = countItems(array, 2); and the implementation details can be argued inside.
– joeytwiddle
Jul 14 '16 at 5:37
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Reasons for using the set.seed function
...s the possible desire for reproducible results, which may for example come from trying to debug your program, or of course from trying to redo what it does:
These two results we will "never" reproduce as I just asked for something "random":
R> sample(LETTERS, 5)
[1] "K" "N" "R" "Z" "G"
R> sa...
How can I stop a Postgres script when it encounters an error?
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I think the solution to add following to .psqlrc is far from perfection
\set ON_ERROR_STOP on
there exists much more simple and convenient way - use psql with parameter:
psql -v ON_ERROR_STOP=1
better to use also -X parameter turning off .psqlrc file usage.
Works perfectly f...
What is the difference between “ is None ” and “ ==None ”
...actually
makes sense; if someone told you to
implement the None object from
scratch, how else would you get it to
compare True against itself?).
Practically-speaking, there is not much difference since custom comparison operators are rare. But you should use is None as a general rule.
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DESTDIR and PREFIX of make
...alling to a temporary directory which is not where the package will be run from. For example this is used when building deb packages. The person building the package doesn't actually install everything into its final place on his own system. He may have a different version installed already and not ...
Android Fragments: When to use hide/show or add/remove/replace?
...ill be in the running state of its lifecycle, but its UI has been detached from the window so it's no longer visible. So you could technically still interact with the fragment and reattach its UI later you need to. If you replace the fragment, the you are actually pulling it out of the container a...
How do I convert from int to String?
I'm working on a project where all conversions from int to String are done like this:
20 Answers
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Objective-C class -> string like: [NSArray className] -> @“NSArray”
I am trying to get a string name of a class from the class object itself.
3 Answers
3
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Plotting a list of (x, y) coordinates in python matplotlib
...nd(N)
plt.scatter(x, y)
plt.show()
will produce:
To unpack your data from pairs into lists use zip:
x, y = zip(*li)
So, the one-liner:
plt.scatter(*zip(*li))
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How to convert hex to rgb using Java?
...color to RGB code in Java? Mostly in Google, samples are on how to convert from RGB to hex.
17 Answers
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