Uncertain if this captures your intent
# example doesn't need to be so large
for(i in 1:6){
stringname<-sprintf("%s_%s","MyName",i)
assign(paste(stringname),matrix(data=10,nrow=10,ncol=10)) #Should yield 6 arrays (MyName_1,MyName_2,...,MyName_6)
} -> a
colnames(a)
#> NULL
labs <- letters[1:10]
labs
#> [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j"
colnames(a) <- labs
a
#> a b c d e f g h i j
#> [1,] 10 10 10 10 10 10 10 10 10 10
#> [2,] 10 10 10 10 10 10 10 10 10 10
#> [3,] 10 10 10 10 10 10 10 10 10 10
#> [4,] 10 10 10 10 10 10 10 10 10 10
#> [5,] 10 10 10 10 10 10 10 10 10 10
#> [6,] 10 10 10 10 10 10 10 10 10 10
#> [7,] 10 10 10 10 10 10 10 10 10 10
#> [8,] 10 10 10 10 10 10 10 10 10 10
#> [9,] 10 10 10 10 10 10 10 10 10 10
#> [10,] 10 10 10 10 10 10 10 10 10 10
Created on 2020-09-30 by the reprex package (v0.3.0.9001)