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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...
iPhone UITextField - Change placeholder text color
...olor blackColor];
textField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:placeholderText attributes:@{NSForegroundColorAttributeName: color}];
} else {
NSLog(@"Cannot set placeholder text's color, because deployment target is earlier than iOS 6.0");
// TODO: Add fall-back...
A cron job for rails: best practices?
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I'm using the rake approach (as supported by heroku)
With a file called lib/tasks/cron.rake ..
task :cron => :environment do
puts "Pulling new requests..."
EdiListener.process_new_messages
puts "done."
end
To execute from the command line, this is just "rake cron". This command ...
Can't use Swift classes inside Objective-C
... -Swift.h file, only the bridging headers. So I created it, but it's actually empty.
I can use all my ObjC classes in Swift, but I can't do it vice versa. I marked my swift class with @objc but it didn't help. What can I do now?
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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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What is NSLayoutConstraint “UIView-Encapsulated-Layout-Height” and how should I go about forcing it
...eels like an Apple bug, I think it's probably the right thing to do. Especially in light of the fact that Apple recalculate this constraint and everything does lay out correctly after the error prints.
– Rog
Mar 18 '15 at 12:15
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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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node.js fs.readdir recursive directory search
... search using fs.readdir? I realise that we could introduce recursion and call the read directory function with the next directory to read, but am a little worried about it not being async...
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Merge, update, and pull Git branches without using checkouts
I work on a project that has 2 branches, A and B. I typically work on branch A, and merge stuff from branch B. For the merging, I would typically do:
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