Reputation: 1274
Good afternoon !
I'm trying to implement EM algorithm from scratch. I developed a code that contains :
k=10
w_k=rep(1,k)/k
n_j=rep(0,k)
print(w_k)
data=iris[1:150,-5]
means=sample(1:dim(data)[1],k,replace=FALSE)
means
mu=iris[means,-5]
sigma=cov(data)
print("mu")
mu
print("sigma")
sigma
print("inv")
solve(sigma)
print("mu[1,] ")
as.vector(mu[1,])
as.vector(mu[1,]) %*% solve(sigma) #line of error
Unfortunately , this line gives the follwing error :
Error in as.vector(mu[1, ]) %*% solve(sigma) :
requires numeric/complex matrix/vector arguments
Execution halted
I tried to fix the problem many times by using as.matrix()
but without success.
Thank you in advance for help !
Upvotes: 1
Views: 2028
Reputation: 1274
mu
is a data frame and should be transformed to a matrix.
k=10
w_k=rep(1,k)/k
n_j=rep(0,k)
print(w_k)
data=iris[1:150,-5]
means=sample(1:dim(data)[1],k,replace=FALSE)
means
mu=as.matrix(iris[means,-5])
sigma=cov(data)
print("mu")
mu
print("sigma")
sigma
print("inv")
solve(sigma)
print("mu[1,] ")
is.numeric(mu[1,])
is.matrix(mu[1,])
rbind(mu[1,]) %*% solve(sigma) %*% cbind(mu[1,])
Upvotes: 1
Reputation: 6222
The vector mu
is a data.frame. Try converting that to a matrix.
as.matrix(mu[1,]) %*% solve(sigma)
# Sepal.Length Sepal.Width Petal.Length Petal.Width
#95 16.37781 11.46013 -0.198358 -9.473886
Upvotes: 1