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Mean per group in a data.frame [duplicate]
...columns 3 and 4 of data.frame d, grouping by d$Name, and applying the mean function.
Or, using a formula interface:
aggregate(. ~ Name, d[-2], mean)
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Best programming based games [closed]
...e game in question was definitely Robowar for the Mac. My son had a lot of fun with it and went on to program real robots.
As mentioned earlier by Proud, there is a wiki page for it:
http://en.wikipedia.org/wiki/RoboWar
Although there has not been a lot of activity surrounding the game over the l...
为AppInventor2开发自己的拓展(Extension) - App Inventor 2 拓展 - 清泛IT社区，为创新赋能！
来源中文网文档：https://www.fun123.cn/reference/extensions/aix_dev.html
为什么需要开发拓展？App Inventor 2 是积木式在线安卓开发环境，利用拖拽式的方式实现代码块堆叠，从而完成相应的逻辑。上手很容易，但是由于代码块提供的功能...
android pick images from gallery
...etermined by you on this very class, this is further used on the @Override function onActivityResult(int requestCode, resultCode, Intent data), where it's recommended that you use this constant to check the requestCode parameter before doing any action :)
– Gabcvit
...
Difference between Python datetime vs time modules
...stamping.
If the system additionally runs the network time protocol (NTP) dæmon, one ends up with a pretty solid time base.
Here is the documentation of the time module.
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Implicit “Submit” after hitting Done on the keyboard at the last EditText
...
Simple and effective solution with Kotlin
Extend EditText:
fun EditText.onSubmit(func: () -> Unit) {
setOnEditorActionListener { _, actionId, _ ->
if (actionId == EditorInfo.IME_ACTION_DONE) {
func()
}
true
}
}
Then use the new metho...
How to immediately see compile errors in project tree of IntelliJ Idea?
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@MadsMobæk Thanks, but there is no "Problems" view listed in IntelliJ 12.1.4: !screenshot
– Brent Faust
Jul 11 '13 at 2:01
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Refreshing OAuth token using Retrofit without modifying all calls
...al accessTokenWrapper: AccessTokenWrapper) : Authenticator {
override fun authenticate(route: Route, response: Response): Request? {
val newAccessToken = noneAuthAPI.refreshToken(accessTokenWrapper.getAccessToken()!!.refreshToken).blockingGet()
accessTokenWrapper.saveAccessToken...
Why is Multiple Inheritance not allowed in Java or C#?
...omplexity to the languages while providing too little benefit.
For a more fun and in-depth read, there are some articles available on the web with interviews of some of the language designers. For example, for .NET, Chris Brumme (who worked at MS on the CLR) has explained the reasons why they decid...
In tmux can I resize a pane to an absolute value
...solute position, not making a relative adjustment.
– ændrük
Jan 20 '14 at 18:25
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