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How to learn R as a programming language [closed]
...e that you read "The R Inferno".
There are many good resources on the R homepage, but in particular, read "An Introduction to R" and "The R Language Definition".
Some very closely related stackoverflow questions:
books-for-learning-the-r-language.
what-are-some-good-books-web-resources-and-proje...
MySQL Error 1093 - Can't specify target table for update in FROM clause
...lease see other answers to this question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query,...
Are database triggers evil? [closed]
...y hurt you with unintended (and very mysterious) consequences.
This just means they need to be carefully used for the proper circumstances; which in my experience is limited to relational integrity issues (sometimes with finer granularity than you can get declaratively); and usually not for busine...
What are the differences between the threading and multiprocessing modules?
...ssue: There's a Global Interpreter Lock that prevents two threads in the same process from running Python code at the same time. This means that if you have 8 cores, and change your code to use 8 threads, it won't be able to use 800% CPU and run 8x faster; it'll use the same 100% CPU and run at the ...
When should an IllegalArgumentException be thrown?
I'm worried that this is a runtime exception so it should probably be used sparingly.
Standard use case:
6 Answers
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Creating an object: with or without `new` [duplicate]
...already been asked (say, here ); yet I still don't understand it. So, let me ask it.
2 Answers
...
Angularjs ng-model doesn't work inside ng-if
...l="testb" /> {{testb}}
</div>
<div ng-if="!someothervar">
testc (with ng-if): <input type="checkbox" ng-model="testc" />
</div>
<div ng-if="!someothervar">
object (with ng-if): <input type="checkbox" ng...
Interface vs Abstract Class (general OO)
...d every aspect of them I could think of, but it seems they are waiting for me to mention something specific, and I don't know what it is.
...
erb, haml or slim: which one do you suggest? And why? [closed]
...you work on both HTML and ruby logic, or your designer is ready to learn something new (like HAML) I'd go for HAML. It is a lot more ruby-friendly, reduces char count by much and a lot more readable than ERB.
For example (taken from official HAML site):
In ERB your view will look like this:
<d...
How to Sync iPhone Core Data with web server, and then push to other devices? [closed]
I have been working on a method to sync core data stored in an iPhone application between multiple devices, such as an iPad or a Mac. There are not many (if any at all) sync frameworks for use with Core Data on iOS. However, I have been thinking about the following concept:
...