RinAction - R Data Structure - Matrix

gistfile1.r

#################################
#           Matrix              #
#################################

# Creating Matrices
y <- matrix(1:20, nrow = 5, ncol = 4)
y

# fill by rows
cells <- c(1, 26, 24, 68)
rnames <- c("R1", "R2")
cnames <- c("C1", "C2")
mymatrix <- matrix(cells, nrow = 2, ncol = 2, byrow = TRUE, dimnames = list(rnames, cnames))
mymatrix

# fill by column
mymatrix <- matrix(cells, nrow = 2, ncol = 2, byrow = FALSE,dimnames = list(rnames, cnames))
mymatrix

# Using matrix subscripts

x <- matrix(1:10, nrow = 2)
x
x[2, ]
x[, 2]
x[1, 4]
x[1, c(4, 5)]
x[c(1,2),c(3,4)]