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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially unexpected results when one or more grouping variables are not coded as factors. See examples below:
library(dplyr)
data(iris)
# Add an additional level to Species
iris$Species = factor(iris$Species, levels=c(levels(ir...
JavaScript closures vs. anonymous functions
...ing what is a closure in JS and what isn't. We just want to make sure we really understand it correctly.
12 Answers
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Cache busting via params
... the browser will assume that the source will stay the same next time you call ?v=1.123 and should cache it with that string. So it will remain cached, however your server is set up, until you move to ?v=1.124 or so on.
shar...
jQuery parent of a parent
...ou might try
$(this).parents(':eq(1)');
The .parents(selector) says get all ancestors that match the selector
and the :eq(1) says find the oneth (zero-indexed, so the second) element in the list
share
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How to $http Synchronous call with AngularJS
Is there any way to make a synchronous call with AngularJS?
7 Answers
7
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How to manually send HTTP POST requests from Firefox or Chrome browser?
...ome URLs on a web application I'm working on. For that I would like to manually create HTTP POST requests (meaning I can add whatever parameters I like).
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Altering a column: null to not null
...lumns. This is undesirable for several reasons, so I am looking to update all nulls to 0 and then set these columns to NOT NULL . Aside from changing nulls to 0 , data must be preserved.
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Using ZXing to create an Android barcode scanning app [duplicate]
...de reader application which — via Android's intent mechanism — can be called by other applications who wish to integrate barcode scanning.
The easiest way to do this is to call the ZXing SCAN Intent from your application, like this:
public Button.OnClickListener mScan = new Button.OnClickListe...
How do I get the value of text input field using JavaScript?
...earchTxt"]').value; selected by name
Method 6:
document.querySelectorAll('selector')[whole_number].value which also uses a CSS selector to select elements, but it returns all elements with that selector as a static Nodelist.
For example, document.querySelectorAll('#searchTxt')[0].value; ...
Xcode — what is $(SRCROOT)?
...ferent computer, so I need to update some paths. The library search paths all start with $(SRCROOT) . What does that mean?
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