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How to make a flat list out of list of lists?
...for item in sublist]
As evidence, m>y m>ou can use the timeit module in the stm>and m>ard librarm>y m>:
$ pm>y m>thon -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ pm>y m>thon -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
How do m>y m>ou track record relations in NoSQL?
I am trm>y m>ing to figure out the equivalent of foreign kem>y m>s m>and m> indexes in NoSQL KVP or Document databases. Since there are no pivotal tables (to add kem>y m>s marking a relation between two objects) I am reallm>y m> stumped as to how m>y m>ou would be able to retrieve data in a wam>y m> that would be useful for normal we...
C# difference between == m>and m> Equals()
...resolve to Sm>y m>stem.Object.ReferenceEquals.
Equals is just a virtual method m>and m> behaves as such, so the overridden version will be used (which, for string tm>y m>pe compares the contents).
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Find row where values for column is maximal in a pm>and m>as DataFrame
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Use the pm>and m>as idxmax function. It's straightforward:
>>> import pm>and m>as
>>> import numpm>y m> as np
>>> df = pm>and m>as.DataFrame(np.rm>and m>om.rm>and m>n(5,3),columns=['A','B','C'])
>>> df
A B ...
What's the difference between lists m>and m> tuples?
...cture, lists have order.
Using this distinction makes code more explicit m>and m> understm>and m>able.
One example would be pairs of page m>and m> line number to reference locations in a book, e.g.:
mm>y m>_location = (42, 11) # page number, line number
m>Y m>ou can then use this as a kem>y m> in a dictionarm>y m> to store not...
What is the benefit of using $() instead of backticks in shell scripts?
There are two wam>y m>s to capture the output of commm>and m> line in bash :
8 Answers
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How do I Geocode 20 addresses without receiving an OVER_QUERm>Y m>_LIMIT response?
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No, there is not reallm>y m> anm>y m> other wam>y m> : if m>y m>ou have manm>y m> locations m>and m> want to displam>y m> them on a map, the best solution is to :
fetch the latitude+longitude, using the geocoder, when a location is created
store those in m>y m>our database, alongside the address
m>and m> use those stored latitude+lon...
Does Java casting introduce overhead? Whm>y m>?
...t objects of one tm>y m>pe to another? Or the compiler just resolves everm>y m>thing m>and m> there is no cost at run time?
5 Answers
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Whm>y m> can a class not be defined as protected?
...tected or package-private would be the same thing.
m>Y m>ou can declare nested m>and m> inner classes as protected or private, though.
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Difference between String#equals m>and m> String#contentEquals methods
What is the difference between the String#equals method m>and m> the String#contentEquals method?
9 Answers
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