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Instance variables vs. class variables in Python
...r instance. If there would be more than one instance (which won't happen), all instance should have the same configuration. I wonder which of the following options would be better or more "idiomatic" Python.
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Is gcc std::unordered_map implementation slow? If so - why?
...2531
get : 1565
So std::unordered_map in gcc-4.7 is broken (or my installation, which is an installation of gcc-4.7.0 on Ubuntu - and another installation which is gcc 4.7.1 on debian testing).
I will submit a bug report.. until then: DO NOT use std::unordered_map with gcc 4.7!
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How do I get the logfile from an Android device?
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Logcollector is a good option but you need to install it first.
When I want to get the logfile to send by mail, I usually do the following:
connect the device to the pc.
Check that I already setup my os for that particular device.
Open a terminal
Run adb shell logcat >...
Django admin: How to display a field that is marked as editable=False' in the model?
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+1. Especially if you don't plan to edit the field at all in Admin.
– Manoj Govindan
Oct 19 '10 at 16:05
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Create a menu Bar in WPF?
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Jonathon Reinhart
110k2727 gold badges205205 silver badges283283 bronze badges
answered Mar 30 '12 at 3:56
iondenionden...
javac is not recognized as an internal or external command, operable program or batch file [closed]
...nal or external command... error message.
In a nutshell, you have not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(...
Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
How to Remove ReadOnly Attribute on File Using PowerShell?
...e here? As for Keith's answer, he's using PSCX. Not everyone has those installed and that's not really a case of PowerShell v1 vs. v2.
– Joey
Apr 22 '11 at 9:28
add a comment
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Run a callback only if an attribute has changed in Rails
...93C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 45.2525 4.66231 44.6595 4.66231C43.6264 4.66231 43.1481 5.28821 43.1481 6.59048V11.9512C43.1481 13.2535 43.6264 13.8962 44.6595 13.8962C45.69...
How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...