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How to get first element in a list of tuples?
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12 Answers
12
Active
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Which is better option to use for dividing an integer number by 2?
... of the following techniques is the best option for dividing an integer by 2 and why?
23 Answers
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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...
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...
How to set a Default Route (To an Area) in MVC
... to give you a quick summary of what it actually does: It lets you put a {2} into the location format, which corresponds to the area name, the same way {1} corresponds to the controller name. That's it! That's what we had to write all this code for:
BaseAreaAwareViewEngine.cs
public abstract class...
nginx showing blank PHP pages
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252
For reference, I am attaching my location block for catching files with the .php extension:
l...
Preserving signatures of decorated functions
...wargs)
@args_as_ints
def funny_function(x, y, z=3):
"""Computes x*y + 2*z"""
return x*y + 2*z
print funny_function("3", 4.0, z="5")
# 22
help(funny_function)
# Help on function funny_function in module __main__:
#
# funny_function(x, y, z=3)
# Computes x*y + 2*z
Python 3.4+
func...
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[...
Error while installing json gem 'mkmf.rb can't find header files for ruby'
...rn era update, as stated by mimoralea:
In case that you are using ruby 2.0 or 2.2 (thanks @patrick-davey).
sudo apt-get install ruby2.0-dev
sudo apt-get install ruby2.2-dev
sudo apt-get install ruby2.3-dev
or, generic way:
sudo apt-get install ruby-dev
or
sudo apt-get install ruby`r...
EC2 Instance Cloning
Is it possible to clone a EC2 instance data and all?
7 Answers
7
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