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Generate a random double in a range
...rtain conditions.
It is a good practice to first view the function doc in order to understand it
(https://docs.oracle.com/javase/8/docs/api/java/util/Random.html)
Now that we understand that the returned value of the function nextDouble() is a pseudorandom value between 0.0 and 1.0 we can use it ...
How do MySQL indexes work?
...index type is the B+Tree based index, that stores the elements in a sorted order. Also, you don't have to access the real table to get the indexed values, which makes your query return way faster.
The "problem" about this index type is that you have to query for the leftmost value to use the index....
Find kth smallest element in a binary search tree in Optimum way
...doing the operation in O(n), the worst case since I am planning to do an inorder traversal of the entire tree. But deep down I feel that I am not using the BST property here. Is my assumptive solution correct or is there a better one available ?
...
Android: How can I get the current foreground activity (from a service)?
... the service call an event method on that callback/listener object
Send an ordered broadcast Intent to the activity, with a low-priority BroadcastReceiver as backup (to raise a Notification if the activity is not on-screen) -- here is a blog post with more on this pattern
...
What is the preferred syntax for defining enums in JavaScript?
... some assumptions can no longer be made (that value represents the correct order for the size for example).
Remember, in JavaScript an object is just like a map or hash table. A set of name-value pairs. You can loop through them or otherwise manipulate them without knowing much about them in advan...
Single Line Nested For Loops
... the same as this nested for loop (and, as the tutorial says, note how the order of for and if are the same).
>>> combs = []
>>> for x in [1,2,3]:
... for y in [3,1,4]:
... if x != y:
... combs.append((x, y))
...
>>> combs
[(1, 3), (1, 4), (2, 3), ...
IList vs IEnumerable for Collections on Entities
...th lists of things, should they be exposed as ILists or IEnumerables? E.g. Order has a bunch of OrderLines.
2 Answers
...
Linq to Entities join vs groupjoin
... outer join in LINQ is a GroupJoin, flattened by SelectMany.
2. Preserving order
Suppose the list of parents is a bit longer. Some UI produces a list of selected parents as Id values in a fixed order. Let's use:
var ids = new[] { 3,7,2,4 };
Now the selected parents must be filtered from the parents...
How to get index using LINQ? [duplicate]
...
An IEnumerable is not an ordered set.
Although most IEnumerables are ordered, some (such as Dictionary or HashSet) are not.
Therefore, LINQ does not have an IndexOf method.
However, you can write one yourself:
///<summary>Finds the index of ...
Is there a way to get element by XPath using JavaScript in Selenium WebDriver?
...ath) {
return document.evaluate(path, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
}
console.log( getElementByXpath("//html[1]/body[1]/div[1]") );
<div>foo</div>
https://gist.github.com/yckart/6351935
There's also a great introduction on moz...