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Android Studio Multi-Windows for One Project
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edited Mar 13 '18 at 13:59
anand krish
2,87944 gold badges3030 silver badges4242 bronze badges
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Remove NA values from a vector
..., etc.)
Setting na.rm=TRUE does just what you're asking for:
d <- c(1, 100, NA, 10)
max(d, na.rm=TRUE)
If you do want to remove all of the NAs, use this idiom instead:
d <- d[!is.na(d)]
A final note: Other functions (e.g. table(), lm(), and sort()) have NA-related arguments that use d...
What is the scope of variables in JavaScript?
...function f() {
function g() {
console.log(x)
}
let x = 1
g()
}
f() // 1 because x is hoisted even though declared with `let`!
Function parameter names
Function parameter names are scoped to the function body. Note that there is a slight complexity to this. Functions dec...
How to remove the querystring and get only the url?
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16 Answers
16
Active
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底部提示条使用指导 · App Inventor 2 中文网
...ems = ["买菜", "交电费", "取快递"]
global deleted = ""
when Screen1.Initialize() {
列表显示框1.Elements = items
}
when 列表显示框1.AfterPicking() {
deleted = 列表显示框1.Selection
listRemove(items, 列表显示框1.SelectionIndex)
列表显示框1.Elements = items
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Extract a dplyr tbl column as a vector
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188
With dplyr 0.7.0, you can use pull to get a vector from a tbl.
library("dplyr")
#>
#&g...
What is the PostgreSQL equivalent for ISNULL()
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edited Jan 14 '12 at 2:28
Erwin Brandstetter
439k9696 gold badges809809 silver badges969969 bronze badges
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How to convert URL parameters to a JavaScript object?
... the answer based on the comments.
var search = location.search.substring(1);
JSON.parse('{"' + decodeURI(search).replace(/"/g, '\\"').replace(/&/g, '","').replace(/=/g,'":"') + '"}')
Example
Parse abc=foo&def=%5Basf%5D&xyz=5 in five steps:
decodeURI: abc=foo&def=[asf]&xyz=...
overlay two images in android to set an imageview
...mage, or you can configure a LayerDrawable dynamically in code.
Solution #1 (via XML):
Create a new Drawable XML file, let's call it layer.xml:
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/t" />
<item android:draw...