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Painless way to install a new version of R?
...er, you can specify this in the Rprofile.site file, which you find in the /etc/ directory of your R build. Then it will load automatically every time R loads, and you don't have to worry about that any more. You can just install and load packages from the specified directory.
Finally, I have some s...
Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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is not JSON serializable
...fe tage. stackoverflow.com/a/57939897/4157431
– Rami Alloush
Sep 14 '19 at 23:01
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How can I combine two HashMap objects containing the same types?
...od can be more generic, use varargs and loop to putAll Maps from arguments etc. but I wanted to show a concept.
Also, ImmutableMap and its Builder have few limitations (or maybe features?):
they are null hostile (throw NullPointerException - if any key or value in map is null)
Builder don't accep...
Evaluate expression given as a string
... My point was that people should not use parse(text=.) but rather quote(.) etc, to construct the call which later will be eval()ed.
– Martin Mächler
Aug 6 '19 at 7:43
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How do I cast a variable in Scala?
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The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
@RequestParam vs @PathVariable
...re interesting annotation:
@MatrixVariable
http://localhost:8080/spring_3_2/matrixvars/stocks;BT.A=276.70,+10.40,+3.91;AZN=236.00,+103.00,+3.29;SBRY=375.50,+7.60,+2.07
And the Controller method for it
@RequestMapping(value = "/{stocks}", method = RequestMethod.GET)
public String showPortfo...
Renaming the current file in Vim
...node and change file name. Also there are options like delete, copy, move, etc...
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Iterator invalidation rules
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C++17 (All references are from the final working draft of CPP17 - n4659)
Insertion
Sequence Containers
vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capa...
What is a word boundary in regex?
... be "identifier" characters (alnums and underscore), not as anything especially useful for English.
– hobbs
Aug 24 '09 at 21:02
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