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Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith value in the Btime column you could use:
In ...
What are the drawbacks of Stackless Python? [closed]
...and it seems to have many advantages compared with vanilla cPython. It has all those cool features like infinite recursion, microthreads, continuations, etc. and at the same time is faster than cPython (around 10%, if the Python wiki is to be believed) and compatible with it (at least versions 2...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...d Visual Basic books talk about them to a certain extent, but they never really go into any real detail.
13 Answers
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How does Stack Overflow generate its SEO-friendly URLs?
...I benchmarked it). I figured I'd optimize it because this function can be called hundreds of times per page.
/// <summary>
/// Produces optional, URL-friendly version of a title, "like-this-one".
/// hand-tuned for speed, reflects performance refactoring contributed
/// by John Gietzen (user...
How to test if a string is basically an integer in quotes using Ruby
...z/.match(string_to_check)
#Is not a positive number
else
#Is all good ..continue
end
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Swift - Convert to absolute value
...alue.magnitude) // prints: 5
#2. Get absolute value of an Int from abs(_:) method
Swift has a global numeric function called abs(_:) method. abs(_:) has the following declaration:
func abs<T>(_ x: T) -> T where T : Comparable, T : SignedNumeric
Returns the absolute value of the g...
Read only the first line of a file?
...od (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...
PHP ORMs: Doctrine vs. Propel
...eing the default ORM for symfony it is better supported (even though officially the ORMs are considered equal).
Furthermore I better like the way you work with queries (DQL instead of Criteria):
<?php
// Propel
$c = new Criteria();
$c->add(ExamplePeer::ID, 20);
$items = ExamplePeer::doSelect...
Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...lied to the target database.
Applying explicit migrations: [201402032113124_InitialDatabaseCreation].
Applying explicit migration: 201402032113124_InitialDatabaseCreation.
Running Seed method.
PM> Update-Database -ConfigurationTypeName WebApplication3.Migrations.AnotherDbContext.Configuration
Sp...
If string is empty then return some default value
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ActiveSupport adds a presence method to all objects that returns its receiver if present? (the opposite of blank?), and nil otherwise.
Example:
host = config[:host].presence || 'localhost'
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