How can I assign a matrix to a observation in a data frame in R-CodePudding

I am trying to create a dataframe where one of the columns is essentially a list of matrices, but I am unsure how to do that. My code is essentialy so:

matrix <- matrix(1:45, 18,18)
df$column[observation] <- matrix

This does not work at all, with the observation taking one number as its value, instead of the entire matrix

CodePudding user response：

You can put inside the column as a list, an example:

Code

matrix <- matrix(1:45, 18,18)

df <- data.frame(a = 1)

df$m <- list(matrix)

str(df)

Output

'data.frame':   1 obs. of  2 variables:
 $ a: num 1
 $ m:List of 1
  ..$ : int [1:18, 1:18] 1 2 3 4 5 6 7 8 9 10 ...

CodePudding user response：

As a follow up questions, would you perhaps know how to access a specific element of the list?

You can access elements of the matrices in your list by using index numbers:

m1 <- matrix(1:20, ncol = 4)
m2 <- 5 * m1
m3 <- 10 * m2
list1 <- list(m1, m2, m3)
list1[[2]][3, 3]
# From matrix 2 in the list, get the element indexed at 3, 3
[1] 65