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Split data frame string column into multiple columns
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Use stringr::str_split_fixed
library(stringr)
str_split_fixed(before$type, "_and_", 2)
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Python append() vs. + operator on lists, why do these give different results?
...quences) by concatenating the element. The append-method however does literally what you ask: append the object on the right-hand side that you give it (the array or any other object), instead of taking its elements.
An alternative
Use extend() if you want to use a function that acts similar to the ...
How to create fixed space and flexible space bar button items programmatically?
I want to create UIBarButtonItems programmatically and place these fixed space items between buttons.
7 Answers
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Dynamic instantiation from string name of a class in dynamically imported module?
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You can use getattr
getattr(module, class_name)
to access the class. More complete code:
module = __import__(module_name)
class_ = getattr(module, class_name)
instance = class_()
As mentioned below, we may use importlib
import importlib
module = importlib.imp...
Role/Purpose of ContextLoaderListener in Spring?
...ates the WebApplicationContext. Otherwise it would need to be created manually.
– sourcedelica
Jul 26 '13 at 15:21
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Javascript heredoc
...plicable if you just wanted multi-line strings. However, since you can't really change the symbol that encloses your string, it's not really heredoc.
– Peeyush Kushwaha
Apr 23 '16 at 9:14
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python assert with and without parenthesis
...through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentially called assert True when you wr...
How do I convert a Vector of bytes (u8) to a string
...("result: {}", s);
}
The conversion is in-place, and does not require an allocation. You can create a String from the string slice if necessary by calling .to_owned() on the string slice (other options are available).
The library reference for the conversion function:
std::str::from_utf8
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How to get a reference to current module's attributes in Python
...he way I typically see this done is like this:
import sys
dir(sys.modules[__name__])
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Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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