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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 ...
Spring Test & Security: How to mock authentication?
...e properly secured. Just in case someone changes things around and accidentally removes security settings.
7 Answers
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What is the standard naming convention for html/css ids and classes?
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There isn't one.
I use underscores all the time, due to hyphens messing up the syntax highlighting of my text editor (Gedit), but that's personal preference.
I've seen all these conventions used all over the place. Use the one that you think is best - the one...
How to construct a REST API that takes an array of id's for the resources
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If you are passing all your parameters on the URL, then probably comma separated values would be the best choice. Then you would have an URL template like the following:
api.com/users?id=id1,id2,id3,id4,id5
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How to get a subset of a javascript object's properties
...og(picked); // { a: 5, c: 7 }
From Philipp Kewisch:
This is really just an anonymous function being called instantly. All of this can be found on the Destructuring Assignment page on MDN. Here is an expanded form
let unwrap = ({a, c}) => ({a, c});
let unwrap2 = function({a, ...
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...
How is pattern matching in Scala implemented at the bytecode level?
...atterns like or patterns and combinations like "case Foo(45, x)", but generally those are just logical extensions of what I just described. Patterns can also have guards, which are additional constraints on the predicates. There are also cases where the compiler can optimize pattern matching, e.g...
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...
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...
How to add “active” class to Html.ActionLink in ASP.NET MVC
...ges, it would be smart to have a way to apply that selected class automatically based on the current page rather than copy the menu multiple times and do it manually.
The easiest way is to simply use the values contained in ViewContext.RouteData, namely the Action and Controller values. We could b...