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Appropriate datatype for holding percent values?
...The OP showed 2 decimal places so I assumed that 99.99% and 100.00% are valid values. If you want percents with 0 decimal places, then you can use decimal(3,2) to store them as fractions or a tinyint if you are going to store whole numbers.
– Thomas
Apr 14 '18 ...
How to check if my string is equal to null?
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If myString is null, then calling myString.equals(null) or myString.equals("") will fail with a NullPointerException. You cannot call any instance methods on a null variable.
Check for null first like this:
if (myString != null && !myString....
How to create a bash script to check the SSH connection?
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ssh -q -o "BatchMode=yes" -i /home/sicmapp/.ssh/id_rsa <ID>@<Servername>.<domain> "echo 2>&1" && echo $host SSH_OK || echo $host SSH_NOK
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Python circular importing?
...nction. An import is just a command like any other (assignment, a function call, def, class). Assuming your imports occur at the top of the script, then here's what's happening:
When you try to import World from world, the world script gets executed.
The world script imports Field, which causes th...
static linking only some libraries
How can I statically link only a some specific libraries to my binary when linking with GCC?
8 Answers
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Move assignment operator and `if (this != &rhs)`
...rhs);
return lhs;
}
If dumb_array's clients value speed, they should call the operator=. If they need strong exception safety, there are generic algorithms they can call that will work on a wide variety of objects and need only be implemented once.
Now back to the original question (which ha...
How to return dictionary keys as a list in Python?
... to doing list(iterable) and its behaviour was initially documented in the Calls section of the Python Reference manual. With PEP 448 the restriction on where *iterable could appear was loosened allowing it to also be placed in list, set and tuple literals, the reference manual on Expression lists w...
What are commit-ish and tree-ish in Git?
...he Short Answer (TL;DR)
Here's a complete list of commit-ish and tree-ish identifiers (from the Git
revisions documentation):
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| Commit-ish/Tree-ish | Examples
-----------------------------------------------...
What does it mean if a Python object is “subscriptable” or not?
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It basically means that the object implements the __getitem__() method. In other words, it describes objects that are "containers", meaning they contain other objects. This includes strings, lists, tuples, and dictionaries.
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How to get a random number in Ruby
...2 + rand(6) + rand(6).
Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug, hence the 1.9.2 target for that feature).
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