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How do I replace NA values with zeros in an R dataframe?
... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1))
Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each.
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What is the smallest possible valid PDF?
... This will not work, you need to define a font resource and select it inside the page content for the text to show up.
– yms
Aug 21 '15 at 20:36
...
App Inventor 2 扩展 · App Inventor 2 中文网
...component to an extension using the App Inventor Extension Template.
This selection list some issues to keep in mind.
3.3.1 When you start to build
You can follow the method described above and begin by creating an ordinary component on a local instance of App Inventor, together with an app that ...
How exactly does the “Specific Version” property of an assembly reference work in Visual Studio?
...u examine the properties of an assembly reference in the Visual Studio UI (select the reference and hit F4), the value you see for the "Specific Version" property tells you whether or not Visual Studio is going to perform the "Specific Version" check. In case 6 the UI will show "True", although the ...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
... ⇺ ⇻ ⇼ ⇽ ⇾ ⇿
Additional HTML unicode symbols
A selected list of other helpful Unicode icons/symbols.
U+2302 ⌂ HOUSE
U+2303 ⌃ UP ARROWHEAD
U+2304 ⌄ DOWN ARROWHEAD
U+2305 ⌅ PROJECTIVE
U+2306 ⌆ PERSPECTIVE
U+2307 ⌇ WAVY LINE
U+2315 ⌕ TELEP...
How to write a scalable Tcp/Ip based server
... to doubt these indicative figures.
IOCP versus thread-per-connection or 'select' primitives
The reason you want to use a mechanism that uses IOCP under the hood is that it uses a very low-level Windows thread pool that does not wake up any threads until there is actual data on the IO channel that...
What to do Regular expression pattern doesn't match anywhere in string?
...\&_more.htm
input tag #1 at character 9955:
class => "searchSelect"
id => "twotabsearchtextbox"
name => "field-keywords"
size => "50"
style => "width:100%; background-color: #FFF;"
title => "Search for"
type => "text"
...
public friend swap member function
...call:
using std::swap; // allow use of std::swap...
swap(x, y); // ...but select overloads, first
// that is, if swap(x, y) finds a better match, via ADL, it
// will use that instead; otherwise it falls back to std::swap
What is a friend function? There is confusion around this area.
Before C++...
Split string into an array in Bash
...omewhere after 2.05b):
echo "${array[@]: -1:1}"
Larger negative offsets select farther from the end of the array. Note the space before the minus sign in the older form. It is required.
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What is “Argument-Dependent Lookup” (aka ADL, or “Koenig Lookup”)?
...eems a bit backwards. I would expect the problem do be when std::swap() is selected rather than the overload specific to the type, A::swap(). The example with std::swap(A::MyClass&, A::MyClass&) seems misleading. since std would never have a specific overload for a user type, I don't think i...