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What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...: pd.Series(df.Letter.values,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e'}
Speed comparion (using Wouter's method)
In [6]: df = pd.DataFrame(randint(0,10,10000).reshape(5000,2),columns=list('AB'))
In [7]: %timeit dict(zip(df.A,df.B))
1000 loops, best of 3: 1.27 ms...
What is the bower (and npm) version syntax?
...
342
In a nutshell, the syntax for Bower version numbers (and NPM's) is called SemVer, which is short...
What is the syntax to insert one list into another list in python?
...
Do you mean append?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x.append(y)
>>> x
[1, 2, 3, [4, 5, 6]]
Or merge?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x + y
[1, 2, 3, 4, 5, 6]
>>> x.extend(y)
>>...
How do you plot bar charts in gnuplot?
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124
Simple bar graph:
set boxwidth 0.5
set style fill solid
plot "data.dat" using 1:3:xtic(2) wi...
Can I keep Nuget on the jQuery 1.9.x/1.x path (instead of upgrading to 2.x)?
...support for several browsers should have been made into a separate version 2 nuget package and advertised accordingly, i.e. with significant disclaimers. The 1.9 library is not legacy and will receive further updates in the future. I've been in touch with the package author and will write more if I ...
Append a NumPy array to a NumPy array
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234
In [1]: import numpy as np
In [2]: a = np.array([[1, 2, 3], [4, 5, 6]])
In [3]: b = np.array...
Reset keys of array elements in php?
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296
To reset the keys of all arrays in an array:
$arr = array_map('array_values', $arr);
In cas...
Convert a row of a data frame to vector
...
answered Jan 23 '13 at 16:42
Ben BolkerBen Bolker
160k1919 gold badges286286 silver badges366366 bronze badges
...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
I have seen number ranges represented as [first1,last1) and [first2,last2) .
4 Answers
...
List of lists changes reflected across sublists unexpectedly
...o it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 140560897920048
print(
f"id(l[0]): {id(l[0])}\n"
f"id(l[1]): {id(l[1])}\n"
f"id(l[2]): {id(l[2])}"
)
# id(l[0]): 140560897920048
# id(l[1]): 140560897920048
# id(l[2]): 140560897920048
x[0] = 42
print(f"x: {x}")
# x: [42, ...