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Numpy first occurrence of value greater than existing value
I have a 1D array in numpy and I want to find the position of the index where a value exceeds the value in numpy array.
7 A...
Does the order of LINQ functions matter?
...r result = query.Last();
That requires the whole collection to be sorted and then filtered. If we had a million items, only one of which had a code greater than 3, we'd be wasting a lot of time ordering results which would be thrown away.
Compare that with the reversed operation, filtering first:...
How to make an immutable object in Python?
...butes can be accessed via [0] etc., but at least it's considerably shorter and provides the additional advantage of being compatible with pickle and copy.
namedtuple creates a type similar to what I described in this answer, i.e. derived from tuple and using __slots__. It is available in Python 2....
Get properties and values from unknown object
...you should derive from a common base class or implement a common interface and make the calls on those (you can use the as or is operator to help determine which base class/interface you are working with at runtime).
However, if you don't control these type definitions and have to drive logic based...
Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...s a more complete version that shows more differences between [ (aka test) and [[.
The following table shows that whether a variable is quoted or not, whether you use single or double brackets and whether the variable contains only a space are the things that affect whether using a test with or wit...
What optimizations can GHC be expected to perform reliably?
...ut I don't know what they all are, nor how likely they are to be performed and under what circumstances.
3 Answers
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Python: How to ignore an exception and proceed? [duplicate]
I have a try...except block in my code and When an exception is throw. I really just want to continue with the code because in that case, everything is still able to run just fine. The problem is if you leave the except: block empty or with a #do nothing, it gives you a syntax error. I can't use con...
How to log source file name and line number in Python
Is it possible to decorate/extend the python standard logging system, so that when a logging method is invoked it also logs the file and the line number where it was invoked or maybe the method that invoked it?
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How to search by key=>value in a multidimensional array in PHP
..._r takes its fourth parameter by reference rather than by value; the ampersand & is crucial.
FYI: If you have an older version of PHP then you have to specify the pass-by-reference part in the call to search_r rather than in its declaration. That is, the last line becomes search_r($subarray, $k...
How do I get my C# program to sleep for 50 msec?
...Combination of previous 2
It usually combines processing efficiency of 1. and preciseness + ability to do something of 2.
for 1. - Loose waiting in C#:
Thread.Sleep(numberOfMilliseconds);
However, windows thread scheduler causes acccuracy of Sleep() to be around 15ms (so Sleep can easily wa...