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Numbering rows within groups in a data frame
... , id = seq_len(.N)), by = list(cat)] , times = 1000L)
– hannes101
Jul 28 '17 at 12:23
...
Object.watch() for all browsers?
...eturn true;
}
};
let person = new Proxy({}, validator);
person.age = 100;
console.log(person.age); // 100
person.age = 'young'; // Throws an exception
person.age = 300; // Throws an exception
Old answer from 2015
You could have used Object.observe() from ES7. Here's a polyfill. But Object.o...
Merge/flatten an array of arrays
...
GumboGumbo
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...
Colorizing text in the console with C++
... 35 45
Cyan 36 46
White 37 47
Bright Black 90 100
Bright Red 91 101
Bright Green 92 102
Bright Yellow 93 103
Bright Blue 94 104
Bright Magenta 95 105
Bright Cyan 96 106
Bright White 97 107
Sample code for C/C++ :
#include <iostream>
#i...
How to extract a floating number from a string [duplicate]
...ck for a float by stepping to it directly:
user_input = "Current Level: 1e100 db"
for token in user_input.split():
try:
# if this succeeds, you have your (first) float
print float(token), "is a float"
except ValueError:
print token, "is something else"
# => Would...
Java synchronized static methods: lock on object or class
...ption {
for (int i = 0; i < 10; i++) {
Thread.sleep(100);
System.out.println(Thread.currentThread().getName() + " " + i);
}
}
public synchronized void objLock() throws InterruptedException {
for (int i = 0; i < 10; i++) {
Thr...
How to calculate number of days between two given dates?
...le by 4) then (it is a common Year)
#else if (year is not divisable by 100) then (ut us a leap year)
#else if (year is not disible by 400) then (it is a common year)
#else(it is aleap year)
return (year % 4 == 0 and year % 100 != 0) or year % 400 == 0
def Count_Days(year1, month1, d...
Using two values for one switch case statement
... if (((year % 4 == 0) &&
!(year % 100 == 0))
|| (year % 400 == 0))
numDays = 29;
else
numDays = 28;
break;
default:
System.out.println("In...
Floating View 扩展：悬浮视图扩展，将组件转换为悬浮窗口 · App Inventor 2 中文网
....SetView 视图组件为 HorizontalArrangement1 可点击为true 位置X为100 位置Y为500
2. 音乐播放器悬浮控制
悬浮音乐控制面板：
当 音乐播放器.初始化
调用 FloatingView1.SetView 视图组件为 PlayerControl 可点击为true 位置X为5...
Why is this inline-block element pushed downward?
...
Danield
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answered Feb 15 '12 at 7:21
Gary Lindahl...