# Ruby program for vstack() method in Matrix
   
# Include matrix 
require "matrix"
   
# Initialize a matrix 
mat1 =  Matrix[[1, 21], [31, 18]]
mat2 =  Matrix[[4, 6], [3, 9]]
   
# prints the resultant matrix 
puts  mat1.vstack(mat2)

Matrix[[1, 21], [31, 18], [4, 6], [3, 9]]

# Ruby program for vstack() method in Matrix
   
# Include matrix 
require "matrix"
   
# Initialize a matrix 
mat1 =  Matrix[[3, 5, 9], [10, 19, 123]]
mat2 =  Matrix[[12, 12, 13], [19, 18, 89]]
   
# prints the resultant matrix 
puts  mat1.vstack(mat2)

Matrix[[3, 5, 9], [10, 19, 123], [12, 12, 13], [19, 18, 89]]