Working in R studio

grep names factor table levels get or set names create a factor display a table of counts get or set the levels of a factor There are now three options for populating the elements of a vector, matrix, or array. They can be populated with numeric values, complex values, or character strings. The next chapter introduces a fourth option: logical elements. Exercises Create a 2 x 3 x 2 array named abb of U.S. state abbreviations. Then use the substr function to create a second 2 3 2 array named abb 1 which contains just the first letters of each string in abb