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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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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...
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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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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Default template arguments for function templates
Why are default template arguments only allowed on class templates? Why can't we define a default type in a member function template? For example:
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Calling async method synchronously
...nc().Result;
Note: In some cases, this might lead to a deadlock: Your call to Result blocks the main thread, thereby preventing the remainder of the async code to execute. You have the following options to make sure that this doesn't happen:
Add .ConfigureAwait(false) to your library method or...
How to use __doPostBack()
I'm trying to create an asyncrhonous postback in ASP.NET using __doPostBack() , but I have no idea how to do it. I want to use vanilla JavaScript.
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How to convert boost path type to string?
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You just need to call myPath.string().
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