A Function is said to be periodic with period if for , 2, .... For example, the Sine function is periodic with period (as well as with period , , , etc.).

The Constant Function is periodic with any period for all Nonzero Real Numbers , so there is no concept analogous to the Least Period or a Periodic Point for constant functions.

**References**

Morse, P. M. and Feshbach, H. *Methods of Theoretical Physics, Part I.* New York:
McGraw-Hill, pp. 425-427, 1953.

Spanier, J. and Oldham, K. B. ``Periodic Functions.'' Ch. 36 in *An Atlas of Functions.*
Washington, DC: Hemisphere, pp. 343-349, 1987.

© 1996-9

1999-05-26