Create a Matrix from a List of given Vectors in R Programming

R Programming: Matrix Exercise-6 with Solution

Write a R program to create a matrix from a list of given vectors.

Sample Solution:

R Programming Code:

# Initialize an empty list
l = list()

# Loop through numbers 1 to 5
for (i in 1:5) 
  # Assign a vector to each list element, where the vector consists of the loop index followed by numbers 1 to 4
  l[[i]] <- c(i, 1:4)

# Print a message indicating the list of vectors
print("List of vectors:")

# Print the list of vectors
print(l)

# Combine the list of vectors into a matrix by row-binding them
result = do.call(rbind, l)

# Print a message indicating the new matrix
print("New Matrix:")

# Print the resulting matrix
print(result)

Output:

[1] "List of vectors:"
[[1]]
[1] 1 1 2 3 4

[[2]]
[1] 2 1 2 3 4

[[3]]
[1] 3 1 2 3 4

[[4]]
[1] 4 1 2 3 4

[[5]]
[1] 5 1 2 3 4

[1] "New Matrix:"
     [,1] [,2] [,3] [,4] [,5]
[1,]    1    1    2    3    4
[2,]    2    1    2    3    4
[3,]    3    1    2    3    4
[4,]    4    1    2    3    4
[5,]    5    1    2    3    4            

Explanation:

• Initialize an empty list with l = list(), which will be used to store vectors.
• Loop through numbers 1 to 5: For each number i in the range from 1 to 5, create a vector c(i, 1:4) where i is the current number and 1:4 is a sequence of numbers from 1 to 4. Store each vector in the list l at position i.
• Print a message indicating that the list of vectors will be displayed.
• Print the list of vectors to show the content of the list l, which contains vectors created in the loop.
• Combine the list into a matrix: Use do.call(rbind, l) to row-bind the vectors in the list l into a single matrix and assign it to result.
• Print a message indicating that the new matrix will be displayed.
• Print the resulting matrix to show the matrix result created by row-binding the vectors from the list l.

R Programming Code Editor:

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