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How to round an average to 2 decimal places in PostgreSQL?
...ording to Bryan's response you can do this to limit decimals in a query. I convert from km/h to m/s and display it in dygraphs but when I did it in dygraphs it looked weird. Looks fine when doing the calculation in the query instead. This is on postgresql 9.5.1.
select date,(wind_speed/3.6)::numeri...
Why does int num = Integer.getInteger(“123”) throw NullPointerException?
... is not the name of any system property, as discussed here.
If you want to convert this String to int, then use the method as
int num = Integer.parseInt("123").
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Pick a random value from an enum?
...
I really don't see the point of converting the values() array to an unmodifiable list. The VALUES object is already encapsulated by virtue of being declared private. It would be simpler AND more efficient to make it private static final Letter[] VALUES = ...
How to efficiently build a tree from a flat structure?
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trying to convert this approach to C#.
– hakan
Feb 21 '17 at 11:53
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How to find the duration of difference between two dates in java?
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Alternatively long diffInSeconds = TimeUnit.SECONDS.convert(duration,TimeUnit.MILLSECONDS);
– gerardw
Jul 3 '14 at 16:50
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Best way to read a large file into a byte array in C#?
...Length to int instead of getting the long value of the FileInfo length and converting that.
– vapcguy
Oct 12 '16 at 0:15
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Get Unix Epoch Time in Swift
... to get for a given date
Int(myDate.timeIntervalSince1970)
If you want to convert back from UNIX time epoch to Swift Date time, you can use following
let date = Date(timeIntervalSince1970: unixtEpochTime)
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Any way to declare an array in-line?
...shortArrayOf()
byteArrayOf()
If you already have a Collection and wish to convert it to an array inline, simply use:
collection.toTypedArray()
If you need to coerce an array type, use:
array.toIntArray()
array.toLongArray()
array.toCharArray()
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How do I invoke a Java method when given the method name as a string?
...an.Dog";
Class<?> dogClass = Class.forName(dogClassName); // convert string classname to class
Object dog = dogClass.newInstance(); // invoke empty constructor
String methodName = "";
// with single parameter, return void
methodName = "setName";
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What is object slicing?
... also to the copy constructor). This works because an instance of B can be converted to a const A&, which is what assignment operators and copy-constructors expect their arguments to be.
The benign case
B b;
A a = b;
Nothing bad happens there - you asked for an instance of A which is a copy ...