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Determining whether jQuery has not found any element
...t').length is what you're looking for. (If it finds nothing, this will === 0.) So your conditional statement should probably be:
if($('#id').length) { /* code if found */ } else { /* code if not found */ }
You're getting an object returned from that alert because jQuery (almost) always returns the...
Append column to pandas dataframe
...t; dat2 = pd.DataFrame({'dat2': [7,6]})
> dat1.join(dat2)
dat1 dat2
0 9 7
1 5 6
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Is there a Java equivalent to C#'s 'yield' keyword?
...options I know of is Aviad Ben Dov's infomancers-collections library from 2007 and Jim Blackler's YieldAdapter library from 2008 (which is also mentioned in the other answer).
Both will allow you to write code with yield return-like construct in Java, so both will satisfy your request. The notable ...
What is AssemblyInfo.cs used for?
...tab of the file properties you will see no name,
no description, version 0.0.0.0, etc.
The value associated with assembly:Guid is the ID that will identify
the assembly if it will be exposed as a COM object. So, if your
assembly isn't COM-exposed, you don't need this. It is randomly
gen...
Javascript swap array elements
... = list[y];
list[y] = list[x];
list[x] = b;
Edit hijacking top answer 10 years later with a lot of ES6 adoption under our belts:
Given the array arr = [1,2,3,4], you can swap values in one line now like so:
[arr[0], arr[1]] = [arr[1], arr[0]];
This would produce the array [2,1,3,4]. This is ...
How to see top processes sorted by actual memory usage?
...dsarnold
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How to unstash only certain files?
...e git checkout or git show to restore a specific file.
git checkout stash@{0} -- <filename>
With Git 2.23+ (August 2019), use git restore, which replaces the confusing git checkout command:
git restore -s stash@{0} -- <filename>
That does overwrite filename: make sure you didn't have l...
What does |= (ior) do in Python?
...
Here we apply merge (|) and update (|=) to dicts:
>>> d1 = {"a": 0, "b": 1, "c": 2}
>>> d2 = {"c": 20, "d": 30}
>>> # Merge, |
>>> d1 | d2
{"a": 0, "b": 1, "c": 20, "d": 30}
>>> d1
{"a": 0, "b": 1, "c": 2}
>>> # Update, |=
>>> d1 |=...
Ruby: How to get the first character of a string
...h more readable. For instance, this:
class String
def initial
self[0,1]
end
end
will allow you to use the initial method on any string. So if you have the following variables:
last_name = "Smith"
first_name = "John"
Then you can get the initials very cleanly and readably:
puts first...
How to test multiple variables against a value?
...
+500
You misunderstand how boolean expressions work; they don't work like an English sentence and guess that you are talking about the sam...