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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
中文网（自研/维护）拓展 · App Inventor 2 中文网
...nt
Initialize(verticalArrangement)
Method for Initialize
Initialize_Scroll(verticalScrollArrangement)
Method for Initialize_Scroll
RemoveElement(elementIndex)
Method for RemoveElement
Set(list)
Method for Set
SetElement(elementIndex,element)
Method for SetElement
SetEleme...
How do I output an ISO 8601 formatted string in JavaScript?
...
There is already a function called toISOString():
var date = new Date();
date.toISOString(); //"2011-12-19T15:28:46.493Z"
If, somehow, you're on a browser that doesn't support it, I've got you covered:
if ( !Date.prototype.toISOString ) {
( functi...
How to iterate through all git branches using bash script
How can I iterate through all the local branches in my repository using bash script.
I need to iterate and check is there any difference between the branch and some remote branches.
Ex
...
How JavaScript closures are garbage collected
...e expected behavior.
From Mozilla's Memory management page: "As of 2012, all modern browsers ship a mark-and-sweep garbage-collector." "Limitation: objects need to be made explicitly unreachable".
In your examples where it fails some is still reachable in the closure. I tried two ways to make it...
How to specify new GCC path for CMake
... path /usr/bin/gcc . But it is old, I need a new version of gcc. So I install a new version in a new path /usr/local/bin/gcc .
...
In Python, how does one catch warnings as if they were exceptions?
...ationWarning)
with warnings.catch_warnings(record=True) as w:
# Cause all warnings to always be triggered.
warnings.simplefilter("always")
# Trigger a warning.
fxn()
# Verify some things
assert len(w) == 1
assert issubclass(w[-1].category, DeprecationWarning)
assert ...
Why doesn't Internet Explorer 11 honour conditional comments even when emulating Internet Explorer 8
...14.
In running a few tests myself it does appear that this was fixed and all is running smoothly again for testing the most amazing browser ever produced...Internet Explorer!
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Getting the class name from a static method in Java
...tatic context to mean the current Class in Java, that that "class.xxx" was allowed in either instance or static code to mean this class! The problem with this is that MyClass is verbose and redundant, in the context. But then as much as I like Java it does seem to lean towards verbosity.
...
Where do I set my company name?
...lt, Xcode inserts a company
name something similar to the
following in all new source files (.m
.h etc):
Copyright (c) 2009 MyCompanyName. All
rights reserved.
Changing this reference is as simple
as entering the following from within
a terminal window, replacing
“YourNameH...