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In php, is 0 treated as empty?
...ues you want to regard as true. Just compare the differences between isset and empty and choose the right combination for the right situation.
– deceze♦
Feb 8 '10 at 9:25
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Can I add a custom attribute to an HTML tag?
...o verify this behavior: "If you download the sample files for this article and validate file internal.html, you can see this for yourself. Unfortunately, when you display the file in a browser, the ]> shows up on the screen. There’s no way around this bug, so this approach is right out."
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Why doesn't 'ref' and 'out' support polymorphism?
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UPDATE: I used this answer as the basis for this blog entry:
Why do ref and out parameters not allow type variation?
See the blog page for more commentary on this issue. Thanks for the great question.
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Let's suppose you have classes Animal, Mammal, Reptile, Giraffe, Turtle and Ti...
URL rewriting with PHP
...s route with mod_rewrite
Add a file called .htaccess in your root folder, and add something like this:
RewriteEngine on
RewriteRule ^/?Some-text-goes-here/([0-9]+)$ /picture.php?id=$1
This will tell Apache to enable mod_rewrite for this folder, and if it gets asked a URL matching the regular exp...
Why dict.get(key) instead of dict[key]?
...ctionary.get("bogus") or my_default? I've seen people use it in some cases and I was wondering if there's any advantage of using one instead of the other (other than readability)
– Algorithmatic
Dec 4 '15 at 21:57
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How to return an empty ActiveRecord relation?
If I have a scope with a lambda and it takes an argument, depending on the value of the argument, I might know that there will not be any matches, but I still want to return a relation, not an empty array:
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How to normalize an array in NumPy?
...:
import numpy as np
from sklearn.preprocessing import normalize
x = np.random.rand(1000)*10
norm1 = x / np.linalg.norm(x)
norm2 = normalize(x[:,np.newaxis], axis=0).ravel()
print np.all(norm1 == norm2)
# True
share
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Execute code when Django starts ONCE only?
...ou want to execute code in the top-level urls.py. That module is imported and executed once.
urls.py
from django.confs.urls.defaults import *
from my_app import one_time_startup
urlpatterns = ...
one_time_startup()
sha...
Referring to the null object in Python
...
And the reason for choosing egg is None over egg == None: The latter can be overloaded, and is likely to break when comparing valid object with None (depends on how it's implemented, but you don't expect everyone to take comp...
Detecting iOS / Android Operating system
I've done some research, and this question has come up, but not in the way I intend. I'm building a page for a client that is a QR code landing, which is a place to download an application. So he doesn't have to print out 2 QR codes on a page, I'd like to detect the current operating system (Apple...