Alphabet Soup Prefix Conundrum

[Thomas Okken]

(03-17-2017 06:15 PM)Maximilian Hohmann Wrote:  

(03-17-2017 06:05 PM)rprosperi Wrote:  The 67 and 34C are the only machines with 3 different color shift keys (the 65 has 3 colored shift keys but 2 are the same color), and therefore the busiest keyboards, but there is no other way to cram that number of functions onto keyboards of those sizes.

The Ti59 has almost as many functions as an Hp67 and only needs one "2nd" and one "INV" key to access them. It even has printing functions.

INV helps a lot to declutter the TI-59 keyboard. HP flirted with that approach as well, with the HP-65 having [f] and [f^-1] keys. The downside of INV is extra keystrokes: two keys for sin, three for arcsin, etc., but for the ease of finding functions, that's probably not a great price to pay.

However, I think you're forgetting about the ugliness of the OP function. See http://83.156.189.247/ti58c/download/doc/LRNen.pdf page 74.

To quote this museum, from the HP-41C page:

Quote:Around the time of the HP-67, an article in the Hewlett-Packard Journal, stated that electronic technology was no longer the only limitation of pocket calculator progress. The human interface was becoming an even greater barrier to adding more functionality. The HP-67 was an excellent example of the problem. It had three shift keys and most of its other keys had four functions. HP was running out of keyboard space for new functions, and many users found it difficult write and use numeric-only programs.

I knew the TI-59 and the HP-97 quite well when the HP-41C came out, and the 41C solved the user interface problems of those earlier calculators beautifully.