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Python (and Python C API): __new__ versus __init__
...stion I'm about to ask seems to be a duplicate of Python's use of __new__ and __init__? , but regardless, it's still unclear to me exactly what the practical difference between __new__ and __init__ is.
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How to maintain a Unique List in Java?
... no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element. As implied by its name, this interface models the mathematical set abstraction.
Note: Great care must be exercised if mutable objects are used as set elements...
Wolfram's Rule 34 in XKCD [closed]
...1110. The digit of least significance is zero. This means that if the cell and its neighbors match rule 0 above, it turns white/negative/0/false/whatever. The second least significant digit is one, so if the cell and its neighbors match rule 1 above, it turns black/positive/1/true/whatever`, etc. et...
Using LIMIT within GROUP BY to get N results per group?
...T aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
ViewPager with Google Maps API v2: mysterious black view
...kground on top of the ViewPager inside a FrameLayout:
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent" >
<android.support.v4.view.ViewPager
android:id="@+id/fragment_container"
android:layout_width="match_parent"
and...
Where does the @Transactional annotation belong?
Should you place the @Transactional in the DAO classes and/or their methods or is it better to annotate the Service classes which are calling using the DAO objects? Or does it make sense to annotate both "layers"?
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Configure apache to listen on port other than 80
...ed LISTEN 8079 directive in httpd.conf .
I opened port 8079 in iptables and restarted iptables. I even stopped iptables service.
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How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
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Which particular version of Ubuntu is this and is this Ubuntu Server Edition?
Recent Ubuntu Server Editions (such as 10.04) ship with AppArmor and MySQL's profile might be in enforcing mode by default. You can check this by executing sudo aa-status like so:
# sudo a...
What is the difference between the states selected, checked and activated in Android?
...
The difference between Checked and Activated is actually quite interesting. Even the Google documentation is apologetic (emphasis below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selec...
When should I use Kruskal as opposed to Prim (and vice versa)?
I was wondering when one should use Prim's algorithm and when Kruskal's to find the minimum spanning tree? They both have easy logics, same worst cases, and only difference is implementation which might involve a bit different data structures. So what is the deciding factor?
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