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Fastest Way to Find Distance Between Two Lat/Long Points
... @Quassnoi: A couple corrections: You'll probably want to switch the order of the coordinates to lat, long. Also, longitudinal distances are proportional the cosine of the latitude, not longitude. And you'll want to change it from multiplication to division, so your first coordinate would b...
How to return dictionary keys as a list in Python?
... Note that if you use list(newdict.keys()) that the keys are not in the order you placed them due to hashing order!
– Nate M
Jan 30 '19 at 3:28
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What is the difference between single and double quotes in SQL?
...r to that alias.
For example
(select account_id,count(*) "count of" from orders group by 1)sub
Here is a subquery from an orders table having account_id as Foreign key that I am aggregating to know how many orders each account placed. Here I have given one column any random name as "count of" f...
Difference between EXISTS and IN in SQL?
... will tell you whether a query returned any results. e.g.:
SELECT *
FROM Orders o
WHERE EXISTS (
SELECT *
FROM Products p
WHERE p.ProductNumber = o.ProductNumber)
IN is used to compare one value to several, and can use literal values, like this:
SELECT *
FROM Orders
WHERE Produ...
What does the 'b' character do in front of a string literal?
...ing.
But also used to represent binary data like struct.pack output.
In order to ease the 2.x-to-3.x transition, the b'...' literal syntax was backported to Python 2.6, in order to allow distinguishing binary strings (which should be bytes in 3.x) from text strings (which should be str in 3.x). ...
List comprehension with if statement
...
You got the order wrong. The if should be after the for (unless it is in an if-else ternary operator)
[y for y in a if y not in b]
This would work however:
[y if y not in b else other_value for y in a]
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Command to list all files in a folder as well as sub-folders in windows
...re format (no heading information or summary).
/O List by files in sorted order.
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Ship an application with a database
... Android requires that you create a class that extends SQLiteOpenHelper in order to work with a Sqlite database.)
package android.example;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.content.Context;
import a...
Java Enum Methods - return opposite direction enum
...l as flexible as first approach since adding more fields or changing their order will break our code.
public enum Direction {
NORTH, EAST, SOUTH, WEST;
// cached values to avoid recreating such array each time method is called
private static final Direction[] VALUES = values();
pu...
Java LinkedHashMap get first or last entry
I have used LinkedHashMap because it is important the order in which keys entered in the map.
14 Answers
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