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Can someone explain the traverse function in Haskell?
... with this line, thanks!
– agam
Jun 30 '18 at 5:42
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Array slices in C#
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13
Note using Array.Copy performs a lot faster than using LINQ's Take or Skip methods.
– Michael
Jun 23 ...
How do you validate a URL with a regular expression in Python?
...n and have been beating my head against the following problem for the past 3 days.
12 Answers
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String.format() to format double in java
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answered Feb 3 '11 at 11:04
David TangDavid Tang
84.3k2828 gold badges156156 silver badges144144 bronze badges
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How to access the ith column of a NumPy multidimensional array?
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>>> test[:,0]
array([1, 3, 5])
Similarly,
>>> test[1,:]
array([3, 4])
lets you access rows. This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It's certainly much quicker tha...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...ies(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 per loo...
In c# is there a method to find the max of 3 numbers?
Like Math.Max but takes 3 or params of int?
10 Answers
10
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What's the difference between eval, exec, and compile?
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3 Answers
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Active
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Is there a performance gain in using single quotes vs double quotes in ruby?
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$ ruby -v
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.0.0]
$ cat benchmark_quotes.rb
# As of Ruby 1.9 Benchmark must be required
require 'benchmark'
n = 1000000
Benchmark.bm(15) do |x|
x.report("assign single") { n.times do; c...
Generate 'n' unique random numbers within a range [duplicate]
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396
If you just need sampling without replacement:
>>> import random
>>> random...