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What is the difference between & and && in Java?

...the first operand evaluates to false since the result will be false (x != 0) & (1/x > 1) <-- this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an exception. (x != 0) && (1/x > 1) <-- this means evaluate (x...
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R programming: How do I get Euler's number?

... 150 The R expression exp(1) represents e, and exp(2) represents e^2. This works because exp i...
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How to remove space between axis & area-plot in ggplot2?

... to expand the scale by 5% on each side for continuous variables, and by 0.6 units on each side for discrete variables. The problem is thus solved by adding expand = c(0,0) to scale_x_continuous and scale_y_continuous. This also removes the need for adding the panel.margin parameter. The code...
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Replace Default Null Values Returned From Left Outer Join

I have a Microsoft SQL Server 2008 query that returns data from three tables using a left outer join. Many times, there is no data in the second and third tables and so I get a null which I think is the default for left outer join. Is there a way to replace the default values in the select stateme...
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栈和队列的面试题Java实现 - 更多技术 - 清泛网 - 专注C/C++及内核技术

... Queue queue = new Queue(); //入队操作 for (int i = 0; i < 5; i++) { queue.add(i); } //出队操作 System.out.println(queue.pop()); System.out.println(queue.pop()); System.out.println(queue.pop()); } } 运...
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Booleans, conditional operators and autoboxing

...onditional expression is the result of applying capture conversion (§5.1.10) to lub(T1, T2) (§15.12.2.7). S1 == &lt;special null type&gt; (see §4.1) S2 == boolean T1 == box(S1) == &lt;special null type&gt; (see last item in list of boxing conversions in §5.1.7) T2 == box(S2) == `Boolean lub(...
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What are the differences between numpy arrays and matrices? Which one should I use?

... | edited May 7 at 14:10 hashlash 49944 silver badges1313 bronze badges answered Apr 11 at 11:52 ...
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Generate random password string with requirements in javascript

...work? Math.random() // Generate random number, eg: 0.123456 .toString(36) // Convert to base-36 : "0.4fzyo82mvyr" .slice(-8);// Cut off last 8 characters : "yo82mvyr" Documentation for the Number.prototype.toString and strin...
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Multiple INSERT statements vs. single INSERT with multiple VALUES

I'm running a performance comparison between using 1000 INSERT statements: 4 Answers 4...
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How to easily initialize a list of Tuples?

... 305 c# 7.0 lets you do this: var tupleList = new List&lt;(int, string)&gt; { (1, "cow"),...