我想通過使用矩陣代數來計算迴歸係數，找出一個多元迴歸的例子。 #create vectors -- these will be our columns
y <- c(3,3,2,4,4,5,2,3,5,3)
x1 <- c(2,2,4,3,4,4,5,3,3,5)
x2 <- c(3,3,4,4,3,3,4,2,4,4)
#create matrix from vectors
M <-
abstract class Bhanu[-A] { val m:List[A] }
給 error: contravariant type A occurs in covariant position in type => List[A] of value m
abstract class Bhanu[-A] { val m:List[A] }
而 abstract clas
public interface IFoo { }
public abstract class IFooDerived : IFoo { }
public class Foo : IFooDerived { }
public interface IBar { }
public abstract class IBarDerived : IBar { }
public class Bar