We have already used the functions iseq and rseq to generate equally spaced sequences of integers and real numbers. The function repeat is useful for generating sequences with a particular pattern. The general form of a call to repeat is
(repeat list pattern)pattern must be either a single number or a list of numbers of the same length as list. If pattern is a single number then repeat simply repeats list pattern times. For example
> (repeat (list 1 2 3) 2) (1 2 3 1 2 3)If pattern is a list then each element of list is repeated the number of times indicated by the corresponding element of pattern. For example
> (repeat (list 1 2 3) (list 3 2 1)) (1 1 1 2 2 3)In Section 6.2 below I generate the variables density and variety by typing them in directly. Using the repeat function we could have generated them like this:
(def density (repeat (repeat (list 1 2 3 4) (list 3 3 3 3)) 3)) (def variety (repeat (list 1 2 3) (list 12 12 12)))