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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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A CORS POST request works from plain JavaScript, but why not with jQuery?
...eeded with jquery 1.5.2 any more. But if you want to add custom headers or allow the use of credentials (username, password, or cookies, etc), read on.
I think I found the answer! (4 hours and a lot of cursing later)
//This does not work!!
Access-Control-Allow-Headers: *
You need to manually s...
What is Android keystore file, and what is it used for?
... going to use "push data" in your app!
– KapteinMarshall
Sep 4 '13 at 9:43
Is Keystore machine specific ? Or we can u...
What's the best way to store Phone number in Django models
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You might actually look into the internationally standardized format E.164, recommended by Twilio for example (who have a service and an API for sending SMS or phone-calls via REST requests).
This is likely to be the most universal way t...
How to undo 'git reset'?
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Short answer:
git reset 'HEAD@{1}'
Long answer:
Git keeps a log of all ref updates (e.g., checkout, reset, commit, merge). You can view it by typing:
git reflog
Somewhere in this list is the commit that you lost. Let's say you just typed git reset HEAD~ and want to undo it. My reflog look...
What's the best online payment processing solution? [closed]
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You can't really answer this kind of question with a "I like 'insert provide name here'" type answer because like so many things it is a balance and the reasons for choosing a payment processing solution tend to be complex.
Volume / Valu...
How to run a background task in a servlet based web application?
... your job here which should run every 5 seconds.
}
}
Yes, that's really all. The container will automatically pickup and manage it.
EJB unavailable? Use ScheduledExecutorService
If your environment doesn't support EJB (i.e. you're not using not a real Java EE server, but a barebones servle...
How to convert a Hibernate proxy to a real entity object
...e objects and some of them are loaded as proxies due to lazy loading. It's all OK and I don't want to turn lazy loading off.
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Jackson databind enum case insensitive
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In version 2.4.0 you can register a custom serializer for all the Enum types (link to the github issue). Also you can replace the standard Enum deserializer on your own that will be aware about the Enum type. Here is an example:
public class JacksonEnum {
public static enum Da...
Javascript calculate the day of the year (1 - 366)
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This works across Daylight Savings Time changes in all countries (the "noon" one above doesn't work in Australia):
Date.prototype.isLeapYear = function() {
var year = this.getFullYear();
if((year & 3) != 0) return false;
return ((year % 100) != 0 || (year % 4...