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How to pad zeroes to a string?
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2506
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
>>&...
Deny all, allow only one IP through htaccess
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edited Nov 28 '15 at 19:00
Laizer
4,83655 gold badges3838 silver badges6969 bronze badges
answered Dec...
(-2147483648> 0) returns true in C++?
... attempt using unsigned types to represent the value (for example, in C89/90 compilers were required to use unsigned long int, but not in C99 or C++). Implementations are allowed to do anything, since the behavior is undefined anyway.
As a side note, this is the reason why constants like INT_MIN ar...
Is there any way to ignore INSTALL_FAILED_VERSION_DOWNGRADE on application install with the Android
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290
It appears the latest version of adb tools has an "allow downgrade flag" that isn't shown in the...
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...
Date ticks and rotation in matplotlib
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If you prefer a non-object-oriented approach, move plt.xticks(rotation=70) to right before the two avail_plot calls, eg
plt.xticks(rotation=70)
avail_plot(axs[0], dates, s1, 'testing', 'green')
avail_plot(axs[1], dates, s1, 'testing2', 'red')
This sets the rotation property before setting up t...
Mercurial move changes to a new branch
...e extension. Suppose you have a history like this:
@ changeset: 2:81b92083cb1d
| tag: tip
| summary: my new feature: edit file a
|
o changeset: 1:8bdc4508ac7b
| summary: my new feature: add file b
|
o changeset: 0:d554afd54164
summary: initial
This means, revisi...
Cross browser JavaScript (not jQuery…) scroll to top animation
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20 Answers
20
Active
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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 ...
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...