How to Create a Matrix in R with Custom Column and Row names?

R Programming: Matrix Exercise-3 with Solution

Write a R program to create a matrix taking a given vector of numbers as input and define the column and row names. Display the matrix.

Sample Solution:

R Programming Code:

# Define the row names for the matrix
row_names = c("row1", "row2", "row3", "row4")

# Define the column names for the matrix
col_names = c("col1", "col2", "col3", "col4")

# Create a 4x4 matrix with numbers from 1 to 16, filled by rows, and assign row and column names
M = matrix(c(1:16), nrow = 4, byrow = TRUE, dimnames = list(row_names, col_names))

# Print a message indicating the matrix is being displayed
print("Original Matrix:")

# Display the created matrix
print(M)

Output:

[1] "Original Matrix:"
     col1 col2 col3 col4
row1    1    2    3    4
row2    5    6    7    8
row3    9   10   11   12
row4   13   14   15   16                

Explanation:

• Define row names: Creates a vector row_names containing four elements: "row1", "row2", "row3", and "row4".
• Define column names: Creates a vector col_names containing four elements: "col1", "col2", "col3", and "col4".
• Create a matrix: Uses the matrix() function to create a 4x4 matrix M filled with numbers from 1 to 16, arranged by rows. The matrix is given row and column names using the dimnames parameter.
• Print a message: Displays the message "Original Matrix:" to indicate that the matrix will be printed next.
• Display the matrix: Prints the created matrix M with the specified row and column names.

R Programming Code Editor:

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