Convert a Matrix to a 1-Dimensional Array in R Programming

R Programming: Matrix Exercise-8 with Solution

Write a R program to convert a matrix to a 1 dimensional array.

Sample Solution:

R Programming Code:

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

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

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

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

# Print the original matrix
print(M)

# Convert the matrix to a 1-dimensional array (column-wise)
result = as.vector(M)

# Print a message indicating the 1D array in column-wise order
print("1 dimensional array (column wise):")

# Print the 1-dimensional array (column-wise)
print(result)

# Convert the matrix to a 1-dimensional array (row-wise) by transposing it first
result = as.vector(t(M))

# Print a message indicating the 1D array in row-wise order
print("1 dimensional array (row wise):")

# Print the 1-dimensional array (row-wise)
print(result)

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
[1] "1 dimensional array (column wise):"
 [1]  1  5  9 13  2  6 10 14  3  7 11 15  4  8 12 16
[1] "1 dimensional array (row wise):"
 [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16                

Explanation:

• Define Row Names:
• row_names = c("row1", "row2", "row3", "row4")
• Creates a vector of row names for the matrix.
• Define Column Names:
• col_names = c("col1", "col2", "col3", "col4")
• Creates a vector of column names for the matrix.
• Create Matrix:
• M = matrix(c(1:16), nrow = 4, byrow = TRUE, dimnames = list(row_names, col_names))
• Constructs a 4x4 matrix with values from 1 to 16. The matrix is filled by rows (byrow = TRUE) and the specified row and column names are assigned.
• Print Original Matrix:
• print("Original Matrix:")
• Outputs a label for the original matrix.
• print(M)
• Displays the content of the original matrix.
• Convert to 1D Array (Column-Wise):
• result = as.vector(M)
• Converts the matrix to a 1-dimensional array, following the column-wise order.
• print("1 dimensional array (column wise):")
• Outputs a label for the column-wise 1D array.
• print(result)
• Displays the 1-dimensional array in column-wise order.
• Convert to 1D Array (Row-Wise):
• result = as.vector(t(M))
• Converts the matrix to a 1-dimensional array after transposing it (to change row-wise to column-wise) and then flattening.
• print("1 dimensional array (row wise):")
• Outputs a label for the row-wise 1D array.
• print(result)
• Displays the 1-dimensional array in row-wise order.

R Programming Code Editor:

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