along a given length n make ascending indices until reaching
the midpoint and descend afterwards again.
Usage
cascade(n, type = 1)
Value
vector (type 1 or 3) or list (type 2)
Arguments
n
integer The length of the indexes
type
(integer, default=1). If 1 the cascade index is returned.
2 returns the index of left and right side, 3 returns the length
of the left and right index vector