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How can I check if my python object is a number? [duplicate]
In Java the numeric types all descend from Number so I would use
5 Answers
5
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How can I convert comma separated string into a List
...ntation yes as the Select extension in this case returns IEnumerable<Int32> and it is not list. However list has a constructor accepting another collection as source.
– Oybek
Feb 15 '12 at 21:07
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What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
How can I determine installed SQL Server instances and their versions?
...'m trying to determine what instances of sql server/sql express I have installed (either manually or programmatically) but all of the examples are telling me to run a SQL query to determine this which assumes I'm already connected to a particular instance.
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How to delete the last n commits on Github and locally?
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edited Feb 12 '17 at 23:32
tulians
40944 silver badges2121 bronze badges
answered Aug 2 '16 at 14:53
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How to validate an email address in PHP
...($email, FILTER_VALIDATE_EMAIL)) {
// invalid emailaddress
}
Additionally you can check whether the domain defines an MX record:
if (!checkdnsrr($domain, 'MX')) {
// domain is not valid
}
But this still doesn't guarantee that the mail exists. The only way to find that out is by sending ...
Opening Vim help in a vertical split window
... when I run :help ____ it always opens like that?
– Tallboy
May 7 '12 at 20:37
13
@Tallboy Try cn...
How to create a directory using nerdtree
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
How does the MapReduce sort algorithm work?
... 1 sampled keys that define the key range for each reduce. In particular, all keys such that sample[i − 1] <= key < sample[i] are sent to reduce i. This guarantees that the output of reduce i are all less than the output of reduce i+1."
So their trick is in the way they determine the keys ...
In Visual Studio C++, what are the memory allocation representations?
In Visual Studio, we've all had "baadf00d", have seen seen "CC" and "CD" when inspecting variables in the debugger in C++ during run-time.
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