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Append integer to beginning of list in Python [duplicate]
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>>>var=7
>>>array = [1,2,3,4,5,6]
>>>array.insert(0,var)
>>>array
[7, 1, 2, 3, 4, 5, 6]
How it works:
array.insert(index, value)
Insert an item at a given position. The first argument is the index of the element before which to in...
How does Dijkstra's Algorithm and A-Star compare?
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47
@MennoGouw: Yes Dijkstra's algorithm was developed first; but it is a special case of the more general algorithm A*. It is not at all unusu...
Why do enum permissions often have 0, 1, 2, 4 values?
Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
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Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None)
In [4]: df1
Out[4]:
0
0 1
1 None
Note: what you cannot do recast the DataFrames dtype to allow all datatypes types, using astype, and then the DataFrame fillna method:
df1 = df.astype(object).replace(np.nan, 'Non...
What is the 'pythonic' equivalent to the 'fold' function from functional programming?
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Fred FooFred Foo
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How do you round to 1 decimal place in Javascript?
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Math.round(num * 10) / 10 works, here is an example...
var number = 12.3456789
var rounded = Math.round(number * 10) / 10
// rounded is 12.3
if you want it to have one decimal place, even when that would be a 0, then add...
var fixed = rounded.toFixed(1)
// fixed is always to 1 d.p.
// NOTE: ....
Fastest way to flatten / un-flatten nested JSON objects
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BergiBergi
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JPA - Returning an auto generated id after persist()
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JB NizetJB Nizet
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10...
Generate unique random numbers between 1 and 100
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answered Mar 4 '10 at 14:45
adam0101adam0101
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Changing UIButton text
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248
When laying out its subviews, a UIButton will set its titleLabel's text value using its own tit...