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Update R using RStudio
...ren't already in the destination directory. i.e. don't overwrite your new 'base' package with your old one - if you did, don't worry, we'll fix it in the next step anyway. If those paths don't work for you, try using installed.packages()
to find the proper pathnames.]
now you can update your package...
__proto__ VS. prototype in JavaScript
...hods to prototype object? This will work if f.__proto__ = g where g is the base class.
– abhisekp
Jul 1 '16 at 16:08
M...
Why does Math.Floor(Double) return a value of type Double?
...for scientific calculations, this answer is not correct because double has 64 bits and long also has 64 bits, but double can not store exact digits of lower significant bits even if it can be stored correctly in long.
– Akash Kava
Aug 28 '09 at 20:18
...
Do any JVM's JIT compilers generate code that uses vectorized floating point instructions?
..." OpenJDK Runtime Environment (IcedTea6 1.10.6) (fedora-63.1.10.6.fc15-x86_64) OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode)
– Samuel Audet
May 30 '12 at 3:34
...
Check play state of AVPlayer
...timeControlStatus
For example, this function plays or pauses the avPlayer based on it's status and updates the play/pause button appropriately.
@IBAction func btnPlayPauseTap(_ sender: Any) {
if aPlayer.timeControlStatus == .playing {
aPlayer.pause()
btnPlay.setImage(UIImage(na...
Fast Linux File Count for a large number of files
...ut 50 times each against the same directory, over and over, to avoid cache-based data skew, and I got roughly the following performance numbers (in real clock time):
ls -1 | wc - 0:01.67
ls -f1 | wc - 0:00.14
find | wc - 0:00.22
dircnt | wc - 0:00.04
That last one, dircnt, is the program compi...
Truncating floats in Python
...using the IEEE floating-point format into the sequence of bits (assuming a 64-bit float)
0011111111010011001100110011001100110011001100110011001100110011
This is the closest value to 0.3 that can accurately be represented as an IEEE float. But if you write 0.29999999999999998 in a Python program,...
How to make git mark a deleted and a new file as a file move?
...not too severe' means that the new file and old file are >50% 'similar' based on some similarity indexes that git uses.
– pjz
Oct 19 '10 at 20:10
160
...
CSS: How to position two elements on top of each other, without specifying a height?
...ut descendants, into the same row and column.
Please check example below, based on Your HTML. I added only <span> and some colors, so You can see the result.
You can also easily change z-index each of descendant elements, to manipulate its visibility (which one should be on top).
.cont...
C语言结构体里的成员数组和指针 - c++1y / stl - 清泛IT社区，为创新赋能！
...t;p的偏移之所以是0x8而不是0x6，是因为内存对齐了（我在64位系统上）。关于内存对齐，可参看《深入理解C语言》一文。好了，现在你知道为什么原题中会访问到了0x4的地址了吧，因为是相对地址。相对地址有很好多处，其可以...