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Why were pandas merges in python faster than data.table merges in R in 2012?
...
It looks like Wes may have discovered a known issue in data.table when the number of unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (t...
How to unit test an object with database queries
...r
{
public Foo[] GetAllFoos() {
return Foo.GetAll();
}
}
Now in your unit test, you create a mock of FooDataProvider, which allows you to call the method GetAllFoos without having to actually hit the database.
class BarTests
{
public TestGetAllFoos() {
// here we set u...
Format in kotlin string templates
...
Is this available now?
– Ragunath Jawahar
Mar 13 '15 at 8:00
4
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When should one use RxJava Observable and when simple Callback on Android?
...});
The RxJava variant is not much better than the Callback variant. For now, let's ignore the error handling.
Let's take a list of photos:
RxJava:
api.getUserPhotos(userId)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.flatMap(new Func1<List<Photo>, Observab...
Linking R and Julia?
...
The RJulia R package looks quite good now from R. R CMD check runs without warnings or errors (if julia is properly installed).
Biggest TODO in my view is to get Julia to return named lists which constitute the really basic flexible general data structure in R....
Converting timestamp to time ago in PHP e.g 1 day ago, 2 days ago…
...
Function :
function time_elapsed_string($datetime, $full = false) {
$now = new DateTime;
$ago = new DateTime($datetime);
$diff = $now->diff($ago);
$diff->w = floor($diff->d / 7);
$diff->d -= $diff->w * 7;
$string = array(
'y' => 'year',
'...
github locks up mac terminal when using pull command
...a modal text editor, so you would need to:
Press i to enter insert mode.
Now you can type your message, as if you were in a normal
(non-modal) text editor.
Press esc to go back to command mode.
Then type :w followed by enter to save.
Finally :q followed by enter to quit.
...
How to delete images from a private docker registry?
...ans that an image is based on another image:
A <- B <- C <- D
Now we add tags to the picture:
A <- B <- C <- D
| |
| <version2>
<version1>
Here, the tag <version1> references the image C and the tag <version2> r...
How to increment a datetime by one day?
... accomplished using timedelta objects:
import datetime
datetime.datetime.now() + datetime.timedelta(days=1)
Look up timedelta objects in the Python docs: http://docs.python.org/library/datetime.html
share
|
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Is there a quicker / better way to clear the iPhone Simulator cache than deleting its directory?
...o the Keyboard Shortcut:. (I use command-period)
Click the Add button.
Now, while in your iOS Simulator, you can simply use your new shortcut key to reset.
If the Simulator doesn't appear in the drop down list:
In a Finder window, go to your Applications folder.
Right-click Xcode and choose...