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What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
...e keys are valid Python identifiers.
This works:
a = {'import': 'trade', 1: 7.8}
a = dict({'import': 'trade', 1: 7.8})
This won't work:
a = dict(import='trade', 1=7.8)
>> SyntaxError: invalid syntax ^
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What is meant by 'first class object'?
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11 Answers
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get NSDate today, yesterday, this Week, last Week, this Month, last Month… variables
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12 Answers
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Django dynamic model fields
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281
As of today, there are four available approaches, two of them requiring a certain storage backen...
How do I test if a variable is a number in Bash?
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842
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How to use a variable for the key part of a map
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169
Use this:
def map = [(A):1, (X):2]
For the value-part it's even easier, since there is no a...
Count number of rows within each group
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14 Answers
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Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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Take the content of a list and append it to another list
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You probably want
list2.extend(list1)
instead of
list2.append(list1)
Here's the difference:
>>> a = range(5)
>>> b = range(3)
>>> c = range(2)
>>> b.append(a)
>>> b
[0, 1, 2, [0, 1, 2, 3, 4]]
>>> c.ex...