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JQuery - $ is not defined
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That error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may h...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...data frame, which is probably what most readers of this answer will want. For a heatmap, though, you would need to convert this to a true matrix.
library(tidyr)
pivot_wider(tmp, names_from = y, values_from = z)
## # A tibble: 2 x 4
## x a b c
## <fct> <dbl> <dbl> &...
Easiest way to check for an index or a key in an array?
...in Bash manual and the little note
if the colon is omitted, the operator tests only for existence [of parameter]
This answer is actually adapted from the answers for this SO question: How to tell if a string is not defined in a bash shell script?
A wrapper function:
exists(){
if [ "$2"...
How can I use map and receive an index as well in Scala?
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I believe you're looking for zipWithIndex?
scala> val ls = List("Mary", "had", "a", "little", "lamb")
scala> ls.zipWithIndex.foreach{ case (e, i) => println(i+" "+e) }
0 Mary
1 had
2 a
3 little
4 lamb
From: http://www.artima.com/forums/fla...
Is it possible to prevent an NSURLRequest from caching data or remove cached data following a reques
On iPhone, I perform a HTTP request using NSURLRequest for a chunk of data. Object allocation spikes and I assign the data accordingly. When I finish with the data, I free it up accordingly - however instruments doesn't show any data to have been freed!
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How can I pass arguments to a batch file?
I need to pass an ID and a password to a batch file at the time of running rather than hardcoding them into the file.
17 An...
Visually managing MongoDB documents and collections [closed]
I'm using MongoDB in a reporting system and have to delete a whole bunch of test documents. While I don't have too much trouble using the JSON-based command-line tools, it gets extremely tedious to have to keep searching for documents, copy-and-pasting OIDs, etc., especially from a command prompt...
Git diff -w ignore whitespace only at start & end of lines
I love to use git diff -w to ignore whitespace differences. But, I just noticed that it ignores even whitespace differences in the middle of lines. How could I only ignore whitespace differences that come at the start (^) or end ($) of lines?
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What is the difference between '@' and '=' in directive scope in AngularJS?
...erty to the evaluated value of the DOM attribute. If you use title=title1 or title="title1", the value of DOM attribute "title" is simply the string title1. If you use title="{{title}}", the value of the DOM attribute "title" is the interpolated value of {{title}}, hence the string will be whateve...
Static fields on a null reference in Java
static members ( static fields or static methods) in Java are associated with their respective class rather than the objects of this class. The following code attempts to access a static field on a null reference.
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