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How to Correctly Use Lists in R?
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Just to address the last part of your question, since that really points out the difference between a list and vector in R:
Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can ha...
Check if database exists in PostgreSQL using shell
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(4 rows)
Using the naive approach means that searching for a database called "List, "Access" or "rows" will succeed. So we pipe this output through a bunch of built-in command line tools to only search in the first column.
The -t flag removes headers and footers:
my_db | my_user | UTF...
Why are side-effects modeled as monads in Haskell?
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Suppose a function has side effects. If we take all the effects it produces as the input and output parameters, then the function is pure to the outside world.
So, for an impure function
f' :: Int -> Int
we add the RealWorld to the consideration
f :: Int -> RealWorl...
How to create .pfx file from certificate and private key?
I need .pfx file to install https on website on IIS.
15 Answers
15
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getApplication() vs. getApplicationContext()
...nt the Application class you registered in the Manifest, you should never call getApplicationContext() and cast it to your application, because it may not be the application instance (which you obviously experienced with the test framework).
Why does getApplicationContext() exist in the first place...
Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie
...iables will not be set (so you'll need to set them in ~/.bash_profile). Finally, this doesn't seem to work for PATH on El Capitan and Sierra. That needs to be set via 'launchctl config user path ...' and in /etc/paths.
share...
Conversion of a datetime2 data type to a datetime data type results out-of-range value
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What kind of dates do you have in the column?
Do all of them fit within the range of the type?
As an aside, the correct way to get a Type object for the DataColumn constructor is the typeof keyword, which is orders of magnitude faster.
Therefore, to create the column, y...
Form onSubmit determine which submit button was pressed [duplicate]
...no actor is explicitly clicked, the browser will
// automatically choose the first in source-order
// so we do the same here
submitActor = $submitActors[0];
}
console.log(submitActor.name);
// alert(submitActor.name);
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Git merge reports “Already up-to-date” though there is a difference
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The message “Already up-to-date” means that all the changes from the branch you’re trying to merge have already been merged to the branch you’re currently on. More specifically it means that the branch you’re trying to merge is a parent of your current branch. Co...
How to detect responsive breakpoints of Twitter Bootstrap 3 using JavaScript?
... following responsive breakpoints: 768px, 992px and 1200px, representing small, medium and large devices respectively.
29 A...