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Can anyone explain python's relative imports?
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3 Answers
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how to permit an array with strong parameters
I have a functioning Rails 3 app that uses has_many :through associations which is not, as I remake it as a Rails 4 app, letting me save ids from the associated model in the Rails 4 version.
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How to properly check if std::function is empty in C++11?
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Why should I prefer single 'await Task.WhenAll' over multiple awaits?
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edited Jun 25 '19 at 16:31
answered Aug 19 '13 at 10:02
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What is the difference between NaN and None?
...= pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype
Out[13]: dtype('O')
In [14]: s_good.dtype
Out[14]: dtype('float64')
Jeff comments (below) on this:
np.nan allows for vectorized operations; its a float value, while None, by definition, forces object ty...
How can I do string interpolation in JavaScript?
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Since ES6, you can use template literals:
const age = 3
console.log(`I'm ${age} years old!`)
P.S. Note the use of backticks: ``.
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How to hide “Showing 1 of N Entries” with the dataTables.js library
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edited Dec 8 '15 at 10:13
answered Oct 18 '13 at 2:47
BMH...
Find the most common element in a list
...'goose'])
emits:
SL: [('duck', 1), ('duck', 2), ('goose', 0), ('goose', 3)]
item 'duck', count 2, minind 1
item 'goose', count 2, minind 0
goose
As you see, SL is a list of pairs, each pair an item followed by the item's index in the original list (to implement the key condition that, if the "m...
std::vector versus std::array in C++
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std::vector is a template class that encapsulate a dynamic array1, stored in the heap, that gr...
pip install mysql-python fails with EnvironmentError: mysql_config not found
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It seems mysql_config is missing on your system or the installer could not find it.
Be sure mys...