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How to determine if one array contains all elements of another array
...
Perhaps this is easier to read:
a2.all? { |e| a1.include?(e) }
You can also use array intersection:
(a1 & a2).size == a1.size
Note that size is used here just for speed, you can also do (slower):
(a1 & a2) == a1
But I guess the first is more re...
Creating an empty Pandas DataFrame, then filling it?
...utocompletion), but that works with strings as date format, right? The overall approach works though (I changed index to something else).
– Matthias Kauer
Dec 15 '12 at 8:42
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WiX tricks and tips
...include file. Enables re-use, variables are faster to find and (if needed) allows for easier manipulation by an external tool.
Define Platform variables for x86 and x64 builds
<!-- Product name as you want it to appear in Add/Remove Programs-->
<?if $(var.Platform) = x64 ?>
<?defin...
Setting PATH environment variable in OSX permanently
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This worked in EL Capitan. Close all the terminals and open a new terminal to check echo $PATH.
– Prem Ananth C
Apr 3 '16 at 12:25
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Python: One Try Multiple Except
...n) as e:
handle_either_of_3rd_4th_or_5th()
except Exception:
handle_all_other_exceptions()
See: http://docs.python.org/tutorial/errors.html
The "as" keyword is used to assign the error to a variable so that the error can be investigated more thoroughly later on in the code. Also note that...
Determine if an object property is ko.observable
...ce) {
if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false;
if (instance.__ko_proto__ === ko.dependentObservable) return true;
return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain
};
UPDATE: If you are using KO 2...
When should you use constexpr capability in C++11?
... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
...
How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
How to log PostgreSQL queries?
How to enable logging of all SQL executed by PostgreSQL 8.3?
10 Answers
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