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Why does Math.round(0.49999999999999994) return 1?
...cause 0.49999999999999994 has a smaller exponent than 0.5, so when they're added, its mantissa is shifted, and the ULP gets bigger.
The solution
Since Java 7, OpenJDK (for example) implements it thus:4
public static long round(double a) {
if (a != 0x1.fffffffffffffp-2) // greatest double valu...
How to determine if binary tree is balanced?
...arthest empty child. My definition is less strict than that, and therefore admits more trees.
One can also be less strict than my definition; one could say that a balanced tree is one in which the maximum path length to an empty tree on each branch differs by no more than two, or three, or some ot...
What difference is there between WebClient and HTTPWebRequest classes in .NET?
...e, if you want to get the content out of an HttpWebResponse, you have to read from the response stream:
var http = (HttpWebRequest)WebRequest.Create("http://example.com");
var response = http.GetResponse();
var stream = response.GetResponseStream();
var sr = new StreamReader(stream);
var content =...
Naming of ID columns in database tables
... more difficult. It obscures meaning and makes complex queries harder to read as well as requiring you to use aliases to differentiate on the report itself.
Further if someone is foolish enough to use a natural join in a database where they are available, you will join to the wrong records.
If y...
`from … import` vs `import .` [duplicate]
...
g.d.d.cg.d.d.c
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Task not serializable: java.io.NotSerializableException when calling function outside closure only o
... }
def someFunc(a: Int) = a + 1
}
or you make someFunc function instead of a method (functions are objects in Scala), so that Spark will be able to serialize it:
import org.apache.spark.{SparkContext,SparkConf}
object Spark {
val ctx = new SparkContext(new SparkConf().setAppName("test").se...
Can you do this HTML layout without using tables?
Ok, I had a simple layout problem a week or two ago. Namely sections of a page needed a header:
10 Answers
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What's the point of 'meta viewport user-scalable=no' in the Google Maps API
...ng notes in his answer, Chrome for Android (and perhaps others) have taken advantage of the fact that there's no native browser zooming on pages with a viewport tag set like that. This allows them to get rid of the dreaded 300ms delay on touch events that the browser takes to wait and see if your si...
Are email addresses case sensitive?
I've read that by standard first part of e-mail is case sensitive, however I've tried to send e-mail to name@example.com , Name@example.com and NAME@example.com - it has arrived in each case.
...
AngularJS : When to use service instead of factory
...ed creation logic. Since factories are regular functions, we can also take advantage of a new lexical scope to simulate "private" variables. This is very useful as we can hide implementation details of a given service."
(ref: http://www.amazon.com/Mastering-Web-Application-Development-AngularJS/d...