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R Programming - Convert a given Matrix to a List


Write a R program to convert a given matrix to a list.

Sample Solution :

R Programming Code :

# Create a matrix with values from 1 to 10, having 2 rows and 2 columns
m = matrix(1:10, nrow = 2, ncol = 2)

# Print the message indicating the original matrix
print("Original matrix:")

# Print the original matrix
print(m)

# Convert the matrix into a list by splitting it column-wise
l = split(m, rep(1:ncol(m), each = nrow(m)))

# Print the message indicating the list derived from the matrix
print("list from the said matrix:")

# Print the resulting list
print(l)

Output:

[1] "Original matrix:"
     [,1] [,2]
[1,]    1    3
[2,]    2    4
[1] "list from the said matrix:"
$`1`
[1] 1 2

$`2`
[1] 3 4                         

Explanation:

  • Create a Matrix:
    • m = matrix(1:10, nrow = 2, ncol = 2)
      • Creates a 2x2 matrix m with values from 1 to 10. The matrix will have 2 rows and 2 columns.
  • Print Original Matrix:
    • print("Original matrix:")
      • Prints the message "Original matrix:" to indicate the following output is the original matrix.
    • print(m)
      • Prints the matrix m.
  • Convert Matrix to List:
    • l = split(m, rep(1:ncol(m), each = nrow(m)))
      • Converts the matrix m into a list l.
      • The split function is used to split the matrix into a list of vectors, with each vector containing the elements of a column.
      • rep(1:ncol(m), each = nrow(m)) creates a repetition pattern to ensure that each column's elements are grouped together.
  • Print List from Matrix:
    • print("list from the said matrix:")
      • Prints the message "list from the said matrix:" to indicate the following output is the list derived from the matrix.
    • print(l)
      • Prints the list l, which contains the columns of the matrix as separate elements.

R Programming Code Editor:



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