convertIndex            Convert Non-Numeric Index Types to Positive
                        Integers
crochet-package         Implementation Helper for '[' and '[<-' of
                        Custom Matrix-Like Types
extract                 Create an Implementation of [ For Custom
                        Matrix-Like Types
ijtok                   Convert Two-Dimensional Indices i and j to
                        One-Dimensional Index k
ktoij                   Convert One-Dimensional Index k to
                        Two-Dimensional Indices i and j
replace                 Create an Implementation of [<- For Custom
                        Matrix-Like Types
