Expand table or matrix to data frame

Expands a contingency table to a data frame where each observation in the table becomes a single observation in the data frame with corresponding information for each for each combination of the table dimensions.

expand_table(x)

Arguments

x	A table or matrix

Value

A data frame with the table or matrix expanded

Examples

expand_table(diag(3))
#>   Var1 Var2
#> 1    A    A
#> 5    B    B
#> 9    C    C
m <- matrix(c(2, 1, 3, 0, 0, 2), 3)
expand_table(m)
#>     Var1 Var2
#> 1      A    A
#> 1.1    A    A
#> 2      B    A
#> 3      C    A
#> 3.1    C    A
#> 3.2    C    A
#> 6      C    B
#> 6.1    C    B
result <- expand_table(UCBAdmissions)
head(result)
#>        Admit Gender Dept
#> 1   Admitted   Male    A
#> 1.1 Admitted   Male    A
#> 1.2 Admitted   Male    A
#> 1.3 Admitted   Male    A
#> 1.4 Admitted   Male    A
#> 1.5 Admitted   Male    A

# Combine into table again
xtabs(~Admit + Gender + Dept, data=result)
#> , , Dept = A
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted  512     89
#>   Rejected  313     19
#> 
#> , , Dept = B
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted  353     17
#>   Rejected  207      8
#> 
#> , , Dept = C
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted  120    202
#>   Rejected  205    391
#> 
#> , , Dept = D
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted  138    131
#>   Rejected  279    244
#> 
#> , , Dept = E
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted   53     94
#>   Rejected  138    299
#> 
#> , , Dept = F
#> 
#>           Gender
#> Admit      Male Female
#>   Admitted   22     24
#>   Rejected  351    317
#>