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How do I replace a character at a particular index in JavaScript?
...
There is no replaceAt function in JavaScript. You can use the following code to replace any character in any string at specified position:
function rep() {
var str = 'Hello World';
str = setCharAt(str,4,'a');
alert(str);
}
function setCharAt(str,index,chr) {
if(index >...
Suppress warning “Category is implementing a method which will also be implemented by its primary cl
...in it. Ideally, singletons should be injected into code as a protocol, allowing you to switch out the implementation. But if you already have one embedded inside your code, you can add a category of the singleton in your unit test and overide the sharedInstance and the methods you what to control to...
Why does Java's hashCode() in String use 31 as a multiplier?
... subtract instruction. However, if your multiplier is slow this is still a win. Modern processors tend to have fast multipliers so it doesn't make much difference, so long as 32 goes on the correct side.
It's not a great hash algorithm, but it's good enough and better than the 1.0 code (and very mu...
Should a Netflix or Twitter-style web service use REST or SOAP? [closed]
... bigger picture. Talking about envelope bytes is like talking about loop unwinding when comparing a quick-sort to a shell-sort. There are scenarios where SOAP can perform better, and there are scenarios where REST can perform better. Context is everything.
REST gains much of its performance advanta...
Programmer Puzzle: Encoding a chess board state throughout a game
...s “all subsequent legal moves”. The problem also says nothing about knowing the moves up to this point. That’s actually a problem as I’ll explain.
Castling
The game has proceeded as follows:
e4 e5
Nf3 Nc6
Bb5 a6
Ba4 Bc5
The board looks as follows:
White has the option of castling...
How to get a vertical geom_vline to an x-axis of class date?
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on my machine (Win10 with R 3.2.2 and ggplot 1.0.1), I have to coerce the date to POSIXct to get it to align properly: as.POSIXct(as.Date(c("2016-12-01","2017-02-01")))
– Jthorpe
Jul 28 '17 at 17:36
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Why is there no tuple comprehension in Python?
...es return a callable so if I only need to do it once I don't see much of a win vs just using tuple(obj[item] for item in items) directly. In my case I was embedding this into a list comprehension to make a list of tuple records. If I need to do this repeatedly throughout the code then itemgetter l...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...参数），最后选择在交叉验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try dif...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...参数），最后选择在交叉验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try dif...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...参数），最后选择在交叉验证中表现最好的。jmp0xf 译自Edwin Chen
How do you know what machine learning algorithm to choose for your classification problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try dif...