Question

How to get multiple columns of a matrix in R

Answer 1

m <- matrix(1:25, nrow=5)
 
print(m)

columns <- m[, c(1, 3)]

print(columns)
  
  
  
  
# run:
#
#      [,1] [,2] [,3] [,4] [,5]
# [1,]    1    6   11   16   21
# [2,]    2    7   12   17   22
# [3,]    3    8   13   18   23
# [4,]    4    9   14   19   24
# [5,]    5   10   15   20   25
#      [,1] [,2]
# [1,]    1   11
# [2,]    2   12
# [3,]    3   13
# [4,]    4   14
# [5,]    5   15
# 

 

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