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What's the difference between lists enclosed by square brackets and parentheses in Python?
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278
Square brackets are lists while parentheses are tuples.
A list is mutable, meaning you can ch...
Numpy where function multiple conditions
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204
The best way in your particular case would just be to change your two criteria to one criterio...
Split string every nth character?
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>>> line = '1234567890'
>>> n = 2
>>> [line[i:i+n] for i in range(0, len(line), n)]
['12', '34', '56', '78', '90']
share
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How to split a delimited string in Ruby and convert it to an array?
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>> "1,2,3,4".split(",")
=> ["1", "2", "3", "4"]
Or for integers:
>> "1,2,3,4".split(",").map { |s| s.to_i }
=> [1, 2, 3, 4]
Or for later versions of ruby (>= 1.9 - as pointed out by Alex):
>> "1,2,3,4".sp...
How to get first element in a list of tuples?
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12 Answers
12
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How can I create a correlation matrix in R?
I have 92 set of data of same type.
5 Answers
5
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count the frequency that a value occurs in a dataframe column
...ame({'a':list('abssbab')})
df.groupby('a').count()
Out[37]:
a
a
a 2
b 3
s 2
[3 rows x 1 columns]
See the online docs: http://pandas.pydata.org/pandas-docs/stable/groupby.html
Also value_counts() as @DSM has commented, many ways to skin a cat here
In [38]:
df['a'].value_counts()
Out[...
How to do exponential and logarithmic curve fitting in Python? I found only polynomial fitting
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230
For fitting y = A + B log x, just fit y against (log x).
>>> x = numpy.array([1, 7, ...
How to check if a string contains a substring in Bash
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26 Answers
26
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Maximum length for MySQL type text
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772
See for maximum numbers:
http://dev.mysql.com/doc/refman/5.0/en/storage-requirements.html
TINYB...