Covariance, contravariance and invariance describe how the existing type inheritance hierarchy changes when subjected to some transformation (such as usage within generics).
Problem I want to implement an algorithm from an unpublished paper by my supervisor and as part of that, I …
python numpy scipy covariance gaussianHow do I generate a data set consisting of N = 100 2-dimensional samples x = (x1,x2)T ∈ R2 drawn from a 2…
python matrix dataset covariance gaussianIEnumerable<T> is co-variant but it does not support value type, just only reference type. The below simple …
c# .net c#-4.0 covariance contravarianceE.g. why does val list:List[Any] = List[Int](1,2,3) work, but val arr:Array[Any] = Array[Int](1,2,3) fails (because …
arrays list scala covarianceThe IDictionary<TKey, TValue> in .NET 4 / Silverlight 4 does not support covariance, i.e. I can't do a IDictionary&…
.net dictionary .net-4.0 covarianceI would like a Covariant collection whose items can be retrieved by index. IEnumerable is the only .net collection that …
c# .net .net-4.0 covarianceConsider these classes. class Base { ... }; class Derived : public Base { ... }; this function void BaseFoo( std::vector<Base*>vec ) { ... } And …
c++ stl vector covarianceEDIT: Re-written this question based on original answer The scala.collection.immutable.Set class is not covariant in its type …
scala set covariance scala-collectionsCan anyone explain the concept of covariance and contravariance in programming language theory?
java c# programming-languages covariance contravariance