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Where is Java's Array indexOf?
I must be missing something very obvious, but I've searched all over and can't find this method.
13 Answers
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What is the correct way of using C++11's range-based for?
...lt;X> initialization ...]
Elements:
1 3 5 7 9
Without any spurious (and potentially expensive) copy constructor call.
So, when observing elements in a container (i.e., for read-only access),
the following syntax is fine for simple cheap-to-copy types, like int, double, etc.:
for (auto elem ...
Is there a difference between using a dict literal and a dict constructor?
...ch should make it a tiny bit faster
the second looks up dict in locals() and then globals() and the finds the builtin, so you can switch the behaviour by defining a local called dict for example although I can't think of anywhere this would be a good idea apart from maybe when debugging
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generating GUID without hyphen
...ter or digits makes no sense. A guid string representation is hexadecimal, and thus will always (well most likely) contain both.
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What does the “map” method do in Ruby?
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The map method takes an enumerable object and a block, and runs the block for each element, outputting each returned value from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Range are enume...
Detect if a NumPy array contains at least one non-numeric value?
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This should be faster than iterating and will work regardless of shape.
numpy.isnan(myarray).any()
Edit: 30x faster:
import timeit
s = 'import numpy;a = numpy.arange(10000.).reshape((100,100));a[10,10]=numpy.nan'
ms = [
'numpy.isnan(a).any()',
'any(n...
How to check if a String is numeric in Java
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With Apache Commons Lang 3.5 and above: NumberUtils.isCreatable or StringUtils.isNumeric.
With Apache Commons Lang 3.4 and below: NumberUtils.isNumber or StringUtils.isNumeric.
You can also use StringUtils.isNumericSpace which returns true for empty st...
Choose newline character in Notepad++
I notice that when I load a text file, Notepad++ will recognize and use whatever the newline character in that file is, \n or \r\n .
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How to get the primary IP address of the local machine on Linux and OS X? [closed]
I am looking for a command line solution that would return me the primary (first) IP address of the localhost, other than 127.0.0.1
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How does one make a Zip bomb?
...compress that into a ZIP file, make 10 copies, pack those into a ZIP file, and repeat this process 9 times.
This way, you get a file which, when uncompressed completely, produces an absurd amount of data without requiring you to start out with that amount.
Additionally, the nested archives make ...