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How do you round a floating point number in Perl?

.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest route. printf("%.3f", 3.1415926535); # prints 3.142 The POSIX module (part of the standard Perl distribution) implements ceil(), floor(), and a number of other mathematical and trigonometric func...
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What does [:] mean?

...he type of population. If population is a list, this line will create a shallow copy of the list. For an object of type tuple or a str, it will do nothing (the line will do the same without [:]), and for a (say) NumPy array, it will create a new view to the same data. ...
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Asynchronous method call in Python?

I was wondering if there's any library for asynchronous method calls in Python . It would be great if you could do something like ...
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Extracting just Month and Year separately from Pandas Datetime column

... what actually does pd.Datetimeindex do? – JOHN Apr 16 '18 at 5:24 1 ...
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Null coalescing in powershell

...t the Powershell versions involving functions/aliases will always evaluate all arguments. If this is a problem, use the if expression form. share | improve this answer | foll...
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Quickly find whether a value is present in a C array?

...ned assembly language. I tend to take the path of least resistance - for small routines like this, I just write asm code and have a good idea how many cycles it will take to execute. You may be able to fiddle with the C code and get the compiler to generate good output, but you may end up wasting lo...
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How to extract the decision rules from scikit-learn decision-tree?

...sion of sklearn, because some values of tree.tree_.feature are -2 (specifically for leaf nodes). There is no need to have multiple if statements in the recursive function, just one is fine. share | ...
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Bash empty array expansion with `set -u`

...ad. Other patterns, such as ${arr[@]-} or ${arr[@]:0}, are not safe across all major versions of Bash. As the table below shows, the only expansion that is reliable across all modern-ish Bash versions is ${arr[@]+"${arr[@]}"} (column +"). Of note, several other expansions fail in Bash 4.2, includin...
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How to remove an item from an array in AngularJS scope?

... Your issue is not really with Angular, but with Array methods. The proper way to remove a particularly item from an array is with Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current inde...
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Detecting endianness programmatically in a C++ program

... Is this solution really portable? What if CHAR_BIT != 8 ? – zorgit May 30 '15 at 20:12  |  ...