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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...
JSONDecodeError: Expecting value: line 1 column 1 (char 0)
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139
To summarize the conversation in the comments:
There is no need to use simplejson library, th...
std::vector versus std::array in C++
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326
std::vector is a template class that encapsulate a dynamic array1, stored in the heap, that gr...
Read .mat files in Python
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edited Jul 24 '19 at 20:23
user8408080
2,10811 gold badge77 silver badges1414 bronze badges
answered Ma...
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...
How can I safely create a nested directory?
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On Python ≥ 3.5, use pathlib.Path.mkdir:
from pathlib import Path
Path("/my/directory").mkdir(parents=True, exist_ok=True)
For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my ...
Insert html in a handlebar template without escaping
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3 Answers
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Rails migrations: Undo default setting for a column
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387
Rails 5+
def change
change_column_default( :table_name, :column_name, from: nil, to: fals...