¹ Available in book form (Blue Ridge Summit, PA: TAB Books, Inc., 1983), 374 pp., $16.50; on disk for the TRS-80, Models III and 4, $35.95; on cassette for the TRS-80, Models I, III, and 4, $30.95. Prices include shipping and handling. Disk and cassette contain programs only with no documentation. The book may be available in local bookstores.

² New York: W.W. Norton & Company, Inc., 1978.

³ New York: John Wiley, 1976.

⁴ See Ruckdeschel, F. R., BASIC Scientific Subroutines, Vol. 1 (New York: Byte/McGraw-Hill, 1981), Chap. IV, $24.50.Google Scholar This volume also contains chapters on plotting subroutines and random number generation.

⁵ David A. Brain, et al. (Rochelle Park: Hayden Books, 1981), 80 pp., $7.95.

⁶ Lines 340–370, pp. 164–165.

⁷ P. 69; this program generates exchange numbers as well as the last four digits randomly. Thus the program's output will not be truly random if exchange numbers are not evenly distributed.

⁸ Brain, et al. mistakenly write that it is between O and whatever number is in the parentheses.

⁹ Brain, p. 67; Barden, William Jr., Programming Techniques for Level II BASIC (Fort Worth: Radio Shack, 1980), p. 68.Google Scholar

¹⁰ Because of copyright restrictions we cannot reproduce the Brain subroutine, but for those who have it, we eliminated the INPUT segments and just used lines 5000–5050 with N=TW/(TD*BP) and Z = 1. The subroutine can be added to the end of the Nickell Survey Estimator program with a GOSUB 5000 added to a line in the main body of the program between lines 280 and 290. Then insert the number generated by the subroutine into line 290 in place of TW/(TD*BP).

¹¹ Brain, et al. indicate that Apple's SET command uses parentheses, e.g., SET(X,Y). This may have been true of an earlier version of Applesoft BASIC, but It does not apply to the He which uses no parentheses.

¹² See Myers, Roy E., Microcomputer Graphics (Reading: Addison-Wesley, 1982), pp. 49–67.Google Scholar