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Convert data.frame columns from factors to characters
... can create a logical vector of which columns are factors, and use that to selectively apply factor
f <- sapply(bobf, class) == "factor"
bobc[,f] <- lapply(bobc[,f], factor)
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How does one generate a random number in Apple's Swift language?
...nteger between 0 and n-1.
let diceRoll = Int(arc4random_uniform(6) + 1)
Cast the result to Int so you don't have to explicitly type your vars as UInt32 (which seems un-Swifty).
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What is the difference between int, Int16, Int32 and Int64?
...ample works that way: the first literal 1, the 2, and the 3 are implicitly cast to short to fit them in the array, while the second literal 1 is left as an ordinary int. (int)1 is not considered equal to (short)1, (short)2, (short)3, thus the result is -1.
– user565869
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How to retrieve the LoaderException property?
...ng it as one type, why create another variable with the same type and do a cast? This should suffice: catch (ReflectionTypeLoadException ex) { var loaderExceptions = ex.LoaderExceptions; }. Also, unless you expect the cast to fail and will check for null, it's better to do a direct cast so it will...
Getting attributes of Enum's value
...
This is a generic implementation using a lambda for the selection
public static Expected GetAttributeValue<T, Expected>(this Enum enumeration, Func<T, Expected> expression)
where T : Attribute
{
T attribute =
enumeration
.GetType()
.GetMe...
How to speed up insertion performance in PostgreSQL
...rypto module) is (a lot) faster than uuid_generate_v4()
=# explain analyze select uuid_generate_v4(),* from generate_series(1,10000);
QUERY PLAN
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Struggling trying to get cookie out of response with HttpClient in .net 4.5
...com");
IEnumerable<Cookie> responseCookies = cookies.GetCookies(uri).Cast<Cookie>();
foreach (Cookie cookie in responseCookies)
Console.WriteLine(cookie.Name + ": " + cookie.Value);
Console.ReadLine();
shar...
What's the difference between ViewData and ViewBag?
...s advantage of the new dynamic features
in C# 4.0. ViewData requires typecasting for complex data type and
check for null values to avoid error. ViewBag doesn’t require
typecasting for complex data type.
ViewBag & ViewData Example:
public ActionResult Index()
{
ViewBag.Name = "...
Get generic type of java.util.List
...)
.flatMap(e->e.getValue().stream())
.map(Number.class::cast)
.collect(Collectors.toList());
This will give you a list of all items whose classes were subclasses of Number which you can then process as you need. The rest of the items were filtered out into other lists. B...
TypeScript: Creating an empty typed container array
...e declaration.
The advantage of using a type assertion (sometimes called a cast, but it's not really a cast in TypeScript) works for any expression, so it can be used even when no variable is declared. There are two syntaxes for type assertions, but only the latter will work in combination with JSX ...