a <- makeCacheMatrix( matrix(c(1,2,12,13), nrow = 2, ncol = 2) );
summary(a);
#> Length Class Mode
#> setMatrix 1 -none- function
#> getMatrix 1 -none- function
#> cacheInverse 1 -none- function
#> getInverse 1 -none- function
a$getMatrix(); #> [,1] [,2] #> [1,] 1 12 #> [2,] 2 13
cacheSolve(a) #> [,1] [,2] #> [1,] -1.1818182 1.09090909 #> [2,] 0.1818182 -0.09090909
cacheSolve(a) #> getting cached data #> [,1] [,2] #> [1,] -1.1818182 1.09090909 #> [2,] 0.1818182 -0.09090909