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What is the most pythonic way to check if an object is a number?
...isinstance(n, Number) (available since 2.6).
>>> from numbers import Number
... from decimal import Decimal
... from fractions import Fraction
... for n in [2, 2.0, Decimal('2.0'), complex(2, 0), Fraction(2, 1), '2']:
... print(f'{n!r:>14} {isinstance(n, Number)}')
2 T...
Design Patterns: Factory vs Factory method vs Abstract Factory
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All three Factory types do the same thing: They are a "smart constructor".
Let's say you want to be able to create two kinds of Fruit: Apple and Orange.
Factory
Factory is "fixed", in that you have just one implementation with no subcla...
The forked VM terminated without saying properly goodbye. VM crash or System.exit called
...lease help me to solve this issue. I do not exactly understand what the error in the log means.
48 Answers
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How do I execute a bash script in Terminal?
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If you already are in the /path/to directory, e.g. with the cd /path/to command, you can enter ./script to run your script.Don't forget, in this case the './' before 'script'
– FrViPofm
Dec 28 '19 at 10:59
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What is the best way to tell if a character is a letter or number in Java without using regexes?
What is the best and/or easiest way to recognize if a string.charAt(index) is an A-z letter or a number in Java without using regular expressions? Thanks.
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vs. . Which to use?
...pirate , let them get a sucky version of your site. Drop IE6, drop IE7, unfortunately IE8 still needs support.
– Jared
Aug 15 '13 at 1:33
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How to run a shell script on a Unix console or Mac terminal?
I know it, forget it and relearn it again. Time to write it down.
7 Answers
7
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Increasing (or decreasing) the memory available to R processes
I would like to increase (or decrease) the amount of memory available to R. What are the methods for achieving this?
6 Ans...
What is the difference between a JavaBean and a POJO?
...ertain conventions. Getter/setter naming, having a public default constructor, being serialisable etc. See JavaBeans Conventions for more details.
A POJO (plain-old-Java-object) isn't rigorously defined. It's a Java object that doesn't have a requirement to implement a particular interface or deriv...
How to count the number of set bits in a 32-bit integer?
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This is known as the 'Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit ...