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Error: could not find function … in R
...hat contains the function? install.packages("thePackage") (this only needs to be done once)
Did you attach that package to the workspace ?
require(thePackage) or library(thePackage) (this should be done every time you start a new R session)
Are you using an older R version where this function didn'...
What is the difference between encrypting and signing in asymmetric encryption?
...
When encrypting, you use their public key to write a message and they use their private key to read it.
When signing, you use your private key to write message's signature, and they use your public key to check if it's really yours.
I want to use my private key to g...
Objective-C: Where to remove observer for NSNotification?
...removeObserver: self] in method dealloc of those classes, which you intend to use as observers, as it is the last chance to unregister an observer cleanly. This will, however, only protect you against crashes due to the notification center notifying dead objects. It cannot protect your code against ...
How do I move forward and backward between commits in git?
I am doing a git bisect and after arriving to the problematic commit, I am now trying to get a step forward/backward to make sure I am in the right one.
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Create a tag in a GitHub repository
I have a repository in GitHub and I need to tag it.
I tagged in a shell, but on GitHub , it is not showing up.
7 Answ...
Google Guice vs. PicoContainer for Dependency Injection
My team is researching dependency injection frameworks and is trying to decide between using Google-Guice and PicoContainer.
...
What is the difference between SAX and DOM?
.../something>), it triggers tagEnded. Using a SAX parser implies you need to handle these events and make sense of the data returned with each event.
In DOM, there are no events triggered while parsing. The entire XML is parsed and a DOM tree (of the nodes in the XML) is generated and returned. On...
How to use the pass statement?
...uppose you are designing a new class with some methods that you don't want to implement, yet.
class MyClass(object):
def meth_a(self):
pass
def meth_b(self):
print "I'm meth_b"
If you were to leave out the pass, the code wouldn't run.
You would then get an:
IndentationE...
Should C# methods that *can* be static be static? [closed]
...t are static because they CAN be
Methods that are static because they HAVE to be
In a small to medium size code base you can really treat the two methods interchangeably.
If you have a method that is in the first category (can-be-static), and you need to change it to access class state, it's rel...
GitHub - failed to connect to github 443 windows/ Failed to connect to gitHub - No Error
Q - I installed git to get the latest version of Angular. When I tried to run
18 Answers
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