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The most sophisticated way for creating comma-separated Strings from a Collection/Array/List?
... was written 11 years ago, but now there are far better options to do this more cleanly in a single line, both using only Java built-in classes or using a utility library. See other answers below.
Since strings are immutable, you may want to use the StringBuilder class if you're going to alter th...
How to test multiple variables against a value?
...long as the size of the tuple is around 4-8 elements. If you have to scan more than that, use a set, but if you are looking for an item out of 2-4 possibilities, a tuple is still faster! If you can arrange for the most likely case to be first in the tuple, the win is even bigger: (my test: timeit....
Difference between “and” and && in Ruby?
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In C#, What is a monad?
...t a; b is basically again a computation that can be combined together with more stuff.
This is a simple monad, it is a way of combing small computations to bigger ones. The ; says "do the thing on the left, then do the thing on the right".
Another thing that can be seen as a monad in object oriente...
What does the “yield” keyword do?
...ion arrives here, the generator will be considered empty
# there is no more than two values: the left and the right children
Caller:
# Create an empty list and a list with the current object reference
result, candidates = list(), [self]
# Loop on candidates (they contain only one element at ...
Oracle SQL: Update a table with data from another table
...ng like @PaulKarr's loop -- and if there is not a unique correlation, then more than one target row may be updated for each source row.
– Andrew Leach
Dec 17 '13 at 16:12
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How can I know if a branch has been already merged into master?
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What is the optimal length for an email address in a database?
...tions here: "but the maximum...restricts the entire email address to be no more than 254 characters"
– RustyTheBoyRobot
Jun 15 '12 at 18:11
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'App not Installed' Error on Android
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Thank you! Android Studio should give more information about this when signing the application, or make it more obvious what it does when you don't tick V1 (Jar Signature)
– melledijkstra
Jan 16 '18 at 15:50
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Save classifier to disk in scikit-learn
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You can also use joblib.dump and joblib.load which is much more efficient at handling numerical arrays than the default python pickler.
Joblib is included in scikit-learn:
>>> import joblib
>>> from sklearn.datasets import load_digits
>>> from sklearn.lin...