Tutorial # 4. Matrix

Matrix is a two dimensional datasets created by using "vector" and defined with its number of rows & columns

nrow => number of rows

ncol => number of Column

byrow = TRUE => arranging row-wise

byrow => FALSE => arranging column-wise

dimnames => Dimension Name

 

my_matrix1 = matrix(c('1','2','3','4','5','6','7','8','9'),

nrow=3, 

ncol =3,

byrow = TRUE)

 

print(my_matrix1)

rows = c('R1' , 'R2' , 'R3' )

cols = c('C1' , 'C2' , 'C3' )

my_matrix2 = matrix(c('1','2','3','4','5','6','7','8','9'),

nrow=3, 

ncol =3, 

byrow = TRUE , 

dimnames = list(rows , cols))

 

print((my_matrix2))

# Making a senquencial number matrix

seq_mat = matrix(1:9, nrow = 3, ncol = 3, byrow = FALSE, dimnames = list(rows,cols))

print(seq_mat)

# Accessing the elements of a matrix => matrix_name[ row , col ]

print(seq_mat[1,1])

print(seq_mat[ ,1])

print(seq_mat[1, ])

print(seq_mat['R1', ])

print(seq_mat[ , 'C1'])

 

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An Introduction to language R

Tutorial # 1.Data Type & Variable  Declaration
Tutorial # 2.Operators
Tutorial # 3.Vector  & Element Access
Tutorial # 4.Matrix
Tutorial # 5.Data Frame

Tutorial # 6.Arrays
Tutorial # 7.Lists
Tutorial # 8.Factors
Tutorial # 9.Data import
Tutorial # 10.Machine Learning
Tutorial # 11.Visualization