|Re: New 15C LE bug?|
Message #2 Posted by Mike Morrow on 5 Feb 2013, 1:46 p.m.,
in response to message #1 by Paul Dale
I only get the results that you describe if a runtime error occurs, such as an overflow when the integration algorithm tries to evaluate x! above about 69. It also appears that the integration routine will never terminate automatically after a runtime error occurs on all flavors of "15C". If no such errors have occurred, a normal display occurs anytime the run is stopped with R/S.
I evaluated your integral from 68 to 69 in fix 4 display (no runtime error expected):
Machine Result Execution Time
HP-15C 3.9792E97 330 seconds
HP 15C-LE 3.9792E97 4 seconds
DM-15CC (48 MHz) 3.9792E97 16 seconds
Runs could be halted with R/S with no display abnormalities.
I evaluated your integral from 69 to 70 in fix 4 display (runtime error *expected*):
These runs did not terminate automatically.
Machine Result after R/S at 400 seconds
HP-15C 5.1602E98 blinking display
HP 15C-LE 2.0638E98 then "running" blinking alternately
DM-15CC (48 MHz) 5.2069E98 blinking display
So, there is a difference between HP 15C-LE results and those of the HP-15C and the more accurately emulated DM-15CC. I think it can be called a bug in the sense that it does not reflect the response of the original HP-15C.