Path: utzoo!utgpu!water!watmath!clyde!rutgers!ames!pasteur!ucbvax!hplabs!hp-pcd!hpcvra!billw
From: billw@hpcvra.HP.COM (Bill Wickes)
Newsgroups: comp.sys.hp
Subject: Re: HP 28S questions
Message-ID: <5040004@hpcvra.HP.COM>
Date: 25 Jan 88 18:31:00 GMT
References: <676@elxsi.UUCP>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 26

There are a number of differences between the HP-28C and HP-28S.  Here's
a brief summary of the modifications/enhancements present in the
28S:

* 32 Kbytes of RAM
* Directory system for USER menu
* Custom menu in which you can combine user variables and built-in commands.
* Save, retrieve and combine LCD pictures/plots.
* Combinations and permutations
* Plotting continues despite math errors/exceptions.
* POS (position) finds an object in a list.
* A(I) returns the Ith element of a list or array, within an algebraic, 
  allowing indexed variables.  A(I,J) works too.
* User defined functions may be defined with programs.
* Command arguments requiring real numbers in lists permit use of
  programs or symbolics in place of the numbers.
* Double-space print mode available.
* Programs decompile and print with automatic indentation to show 
  control structures.
* Single character operators automatically add needed spaces in program entry.
* Press ON-L together to dump LCD image to printer at any time.
* RND (round) works on complex and array objects.
* Singular matrix inversion is tied to the divide-by-zero exception flag.
* Errors automatically identify the guilty command.
* Various 28C bugs fixed.
* Other minor tweaks.