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How do I replace NA values with zeros in an R dataframe?
...want to apply the replacement to specific nurmeric vectors (leaving say... strings with NA): df[19:28][is.na(df[19:28])] <- 0
– jtdoud
Feb 9 '17 at 18:03
...
MVC Razor view nested foreach's model
...s. Lets look at the simplest overload for
TextBoxFor
public static MvcHtmlString TextBoxFor<TModel, TProperty>(
this HtmlHelper<TModel> htmlHelper,
Expression<Func<TModel, TProperty>> expression
)
First, this is an extension method for a strongly typed HtmlHelper,...
Where is Python's sys.path initialized from?
...on is executing is added to sys.path.
On Windows, this is always the empty string, which tells python to
use the full path where the script is located instead.
The contents of PYTHONPATH environment variable, if set, is added to sys.path, unless you're
on Windows and applocal is set to true in pyven...
Easiest way to pass an AngularJS scope variable from directive to controller?
...;
<!-- attribute-foo binds to a DOM attribute which is always
a string. That is why we are wrapping it in curly braces so
that it can be interpolated. -->
<my-component attribute-foo="{{foo}}" binding-foo="foo"
isolated-expression-foo="updateFoo(newFoo)" >
...
Swift and mutating struct
... var)
Consider Swift's Array struct (yes it's a struct).
var petNames: [String] = ["Ruff", "Garfield", "Nemo"]
petNames.append("Harvey") // ["Ruff", "Garfield", "Nemo", "Harvey"]
let planetNames: [String] = ["Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"]
planetNam...
Watermark / hint text / placeholder TextBox
... if (c is ComboBox)
{
return (c as ComboBox).Text == string.Empty;
}
else if (c is TextBoxBase)
{
return (c as TextBox).Text == string.Empty;
}
else if (c is ItemsControl)
{
return (c as ItemsControl).Items...
val-mutable versus var-immutable in Scala
...collection.mutable.ArrayBuffer
object MyObject {
def main(args: Array[String]) {
val a = ArrayBuffer(1,2,3,4)
silly(a)
println(a) // a has been modified here
}
def silly(a: ArrayBuffer[Int]): Unit = {
a += 10
println(s"length: ${a.length}")
...
Why Qt is misusing model/view terminology?
...em to a programmer. Because in most cases the models are simple (e.g. only string lists) Qt also provides a ready-to-use QStringListModel. But if your data is more complex than strings, it's up to you how you want to represent the data via the Qt model/view interface. If you have, for example, a str...
How to create a shared library with cmake?
...none was specified.")
set(CMAKE_BUILD_TYPE "${DEFAULT_BUILD_TYPE}" CACHE STRING "Choose the type of build." FORCE)
# Set the possible values of build type for cmake-gui
set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
endif()
include(GNUIns...
Python read-only property
...m 1: classes thus decorated all end up with an identical __name__, and the string representation of their type is homogenized as well. Problem 2: this decoration overwrites any custom __setattr__. Problem 3: users can defeat this with del MyClass.__setattr__.
– TigerhawkT3
...