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How to implement a Map with multiple keys? [duplicate]
...ey mk, Object k) and then a Map<MetaKey, Map<Object, V>> internally.
– Jeremy Huiskamp
May 4 '09 at 22:21
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How to calculate the angle between a line and the horizontal axis?
...2(deltaY, deltaX) * 180 / PI
EDIT (Feb. 22, 2017): In general, however, calling atan2(deltaY,deltaX) just to get the proper angle for cos and sin may be inelegant. In those cases, you can often do the following instead:
Treat (deltaX, deltaY) as a vector.
Normalize that vector to a unit vector. ...
Entity Framework 6 Code first Default value
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You can do it by manually edit code first migration:
public override void Up()
{
AddColumn("dbo.Events", "Active", c => c.Boolean(nullable: false, defaultValue: true));
}
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Getting visitors country from their IP
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why im getting unknow all the time with every ip ? , used same code.
– echo_Me
Feb 18 '14 at 18:12
1
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Chrome Developer Tools: How to find out what is overriding a CSS rule?
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what if ALL of them are cancelled? Probably due to a script? How do you find out who did it?
– darkgaze
Jun 23 '17 at 8:28
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How to delay the .keyup() handler until the user stops typing?
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I use this small function for the same purpose, executing a function after the user has stopped typing for a specified amount of time or in events that fire at a high rate, like resize:
function delay(callback, ms) {
var timer = 0;
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Multiline strings in JSON
I'm writing some data files in JSON format and would like to have some really long string values split over multiple lines. Using python's JSON module I get a whole lot of errors, whether I use \ or \n as an escape.
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ERROR 2006 (HY000): MySQL server has gone away
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max_allowed_packet=64M
Adding this line into my.cnf file solves my problem.
This is useful when the columns have large values, which cause the issues, you can find the explanation here.
On Windows this file is located at: ...
Does the GitHub traffic graph include your own views?
I have several projects on GitHub, and they all have the traffic graph where I can view how much traffic my repository is getting.
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Automatic creation date for Django model form objects?
What's the best way to set a creation date for an object automatically, and also a field that will record when the object was last updated?
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