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Logical operators for boolean indexing in Pandas
...Error: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True ...
How are Python's Built In Dictionaries Implemented?
...e).
Python dictionaries are implemented as hash tables.
Hash tables must allow for hash collisions i.e. even if two distinct keys have the same hash value, the table's implementation must have a strategy to insert and retrieve the key and value pairs unambiguously.
Python dict uses open addressin...
Why is Thread.Sleep so harmful
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The problems with calling Thread.Sleep are explained quite succinctly here:
Thread.Sleep has its use: simulating lengthy operations while testing/debugging on an MTA thread. In .NET there's no other reason to use it.
Thread.Sleep(n) m...
TypeError: method() takes 1 positional argument but 2 were given
...- it's just that the first one is implicit, from the point of view of the caller.
This is because most methods do some work with the object they're called on, so there needs to be some way for that object to be referred to inside the method. By convention, this first argument is called self inside ...
Catching an exception while using a Python 'with' statement
... print 'oops'
If you want different handling for errors from the open call vs the working code you could do:
try:
f = open('foo.txt')
except IOError:
print('error')
else:
with f:
print f.readlines()
...
Comparing two NumPy arrays for equality, element-wise
...two NumPy arrays for equality (where equality is defined as: A = B iff for all indices i: A[i] == B[i] )?
6 Answers
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Is it possible to import a whole directory in sass using @import?
...rails/sass-rails, features glob importing.
@import "foo/*" // import all the files in the foo folder
@import "bar/**/*" // import all the files in the bar tree
To answer the concern in another answer "If you import a directory, how can you determine import order? There's no way that doesn't...
Flattening a shallow list in Python [duplicate]
...st of iterables with a list comprehension, or failing that, what would you all consider to be the best way to flatten a shallow list like this, balancing performance and readability?
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Should I be using object literals or constructor functions?
....bar;
}
However, this is not favorable with regards to encapsulation: Ideally, all the data + behaviour associated with an entity should live together.
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Undock Chrome Developer Tools
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Click the vertical ellipsis button ( ⋮ ) then choose the desired docking option. (the docking option with the red circle around it, is undock)
For older version of Chrome, press and hold the corner button
You can also undock/dock-to-left/dock-to-right/dock-to-bottom f...