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How do I return multiple values from a function? [closed]
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Well, the design rationale for namedtuple is having a smaller memory footprint for mass results (long lists of tuples, such as results of DB queries). For individual items (if the function in question is not called often) dictionaries and classes are just fine as well. But namedtu...
How to check if a number is a power of 2
...nd only if both its operands are true.
Now let's take a look at how this all plays out:
The function returns boolean (true / false) and accepts one incoming parameter of type unsigned long (x, in this case). Let us for the sake of simplicity assume that someone has passed the value 4 and called ...
How to convert a string from uppercase to lowercase in Bash? [duplicate]
...ing to find a way to convert a string value from upper case to lower case. All the search results show approaches of using tr command.
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Hibernate show real SQL [duplicate]
...logger.org.hibernate.type=TRACE
The first is equivalent to hibernate.show_sql=true, the second prints the bound parameters among other things.
Reference
Hibernate 3.5 Core Documentation
3.5. Logging
Hibernate 4.1 Core Documentation
4.1. Logging
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Get list of a class' instance methods
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You actually want TestClass.instance_methods, unless you're interested in what TestClass itself can do.
class TestClass
def method1
end
def method2
end
def method3
end
end
TestClass.methods.grep(/method1/) # => []
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Error java.lang.OutOfMemoryError: GC overhead limit exceeded
...garbage collector is taking an excessive amount of time (by default 98% of all CPU time of the process) and recovers very little memory in each run (by default 2% of the heap).
This effectively means that your program stops doing any progress and is busy running only the garbage collection at all t...
What does “zend_mm_heap corrupted” mean
All of the sudden I've been having problems with my application that I've never had before. I decided to check the Apache's error log, and I found an error message saying "zend_mm_heap corrupted". What does this mean.
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Why does Java switch on contiguous ints appear to run faster with added cases?
...value has been removed in JDK 8 after more benchmarking was performed.
Finally, when the method becomes too long (> 25 cases in my tests), it is in not inlined any longer with the default JVM settings - that is the likeliest cause for the drop in performance at that point.
With 5 cases, the d...
PostgreSQL error 'Could not connect to server: No such file or directory'
...u are on OS X
Here is the fix:
Stop the database
cd /var
sudo rm -r pgsql_socket
sudo ln -s /tmp pgsql_socket
chown _postgres:_postgres pgsql_socket
Restart PostgreSQL (not your computer)
More information is available at "postgresql 9.0.3. on Lion Dev Preview 1".
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How does Stack Overflow generate its SEO-friendly URLs?
...I benchmarked it). I figured I'd optimize it because this function can be called hundreds of times per page.
/// <summary>
/// Produces optional, URL-friendly version of a title, "like-this-one".
/// hand-tuned for speed, reflects performance refactoring contributed
/// by John Gietzen (user...