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Fast way of counting non-zero bits in positive integer
...1") is the fastest I could find in pure Python.
I tried adapting Óscar's and Adam's solutions to process the integer in 64-bit and 32-bit chunks, respectively. Both were at least ten times slower than bin(n).count("1") (the 32-bit version took about half again as much time).
On the other hand, gm...
Converting a String to DateTime
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Since you are handling 24-hour based time and you have a comma separating the seconds fraction, I recommend that you specify a custom format:
DateTime myDate = DateTime.ParseExact("2009-05-08 14:40:52,531", "yyyy-MM-dd HH:mm:ss,fff",
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Spring JPA selecting specific columns
... answered Feb 25 '14 at 7:43
DurandalDurandal
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How to use Active Support core extensions
I have Active Support 3.0.3 installed and Rails 3.0.3 with Ruby 1.8.7.
5 Answers
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Is there a short contains function for lists?
...m not in list:
# do something
It's work fine for lists, tuples, sets and dicts (check keys).
Note that this is an O(n) operation in lists and tuples, but an O(1) operation in sets and dicts.
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What does JVM flag CMSClassUnloadingEnabled actually do?
...//blogs.oracle.com/poonam/about-g1-garbage-collector,-permanent-generation-and-metaspace Kudos go to mt.uulu
For Java 5-7:
The standard Oracle/Sun VM look on the world is: Classes are forever. So once loaded, they stay in memory even if no one cares anymore. This usually is no problem since you do...
Rake just one migration
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rake db:migrate:redo VERSION=xxxxxxx, but that will run the down and then the up step. You could do this in conjunction with commenting out the down step temporarily.
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Get an object's class name at runtime
...\w+/g)[1];
The above code gets the entire constructor code as a string and applies a regex to get all 'words'. The first word should be 'function' and the second word should be the name of the class.
Hope this helps.
sh...
How can I access getSupportFragmentManager() in a fragment?
I have a FragmentActivity and I want to use a map fragment within it. I'm having a problem getting the support fragment manager to access it.
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How do I restrict a float value to only two places after the decimal point in C?
...e: round down (ie, truncate after two decimal places), rounded to nearest, and round up. Usually, you want round to nearest.
As several others have pointed out, due to the quirks of floating point representation, these rounded values may not be exactly the "obvious" decimal values, but they will b...