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Declaring abstract method in TypeScript
...ed to implement an abstract method as makeSound(input : number) : string { based on the above example where input should be a string. Type 'string' is not assignable to type 'number'..
– Fenton
Dec 6 '17 at 11:50
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Cost of exception handlers in Python
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Calculate distance between 2 GPS coordinates
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Java Version of Haversine Algorithm based on Roman Makarov`s reply to this thread
public class HaversineAlgorithm {
static final double _eQuatorialEarthRadius = 6378.1370D;
static final double _d2r = (Math.PI / 180D);
public static int HaversineI...
What is the purpose of the -m switch?
...ause its package will be loaded along the way. 3) Absolute imports will be based on your current directory, not the directory where the .py file is ('' is at the head of sys.path, rather than /path/to/my, if the script is at /path/to/my/script.py).
– clacke
Sep...
Django - filtering on foreign key properties
I'm trying to filter a table in Django based on the value of a particular field of a ForeignKey .
3 Answers
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How can I make pandas dataframe column headers all lowercase?
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Why can't I use a list as a dict key in python?
...ould just do that instead of relying on __hash__ and __eq__ to be identity-based.
– user395760
Aug 31 '11 at 13:45
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Reading specific lines only
...and you're on. Note that 4 would bring the fifth line as the count is zero-based.
If the file might be very large, and cause problems when read into memory, it might be a good idea to take @Alok's advice and use enumerate().
To Conclude:
Use fileobject.readlines() or for line in fileobject as a ...
What is polymorphism, what is it for, and how is it used?
...ype().Name, v.Wheels));
}
}
In this example, we create a list of the base class Vehicle, which does not know about how many wheels each of its sub-classes has, but does know that each sub-class is responsible for knowing how many wheels it has.
We then add a Bicycle, Car and Truck to the list...
SQL/mysql - Select distinct/UNIQUE but return all columns?
...ery:
SELECT * from table GROUP BY field1;
It will show all your results based on a single instance of field1.
For example, if you have a table with name, address and city. A single person has multiple addresses recorded, but you just want a single address for the person, you can query as follows...