Benchmark test e^x^3

[rprosperi]

(02-12-2019 08:32 PM)Beginner Wrote:  O.K., I´ll try it....

Thanks, this made it easy to follow and reproduce, I get the exact same results as you did ("Error: Invalid input" for range 0..9). I tend to agree there is either a bug in Prime Home mode, or solving this integral is being handed to the CAS for some non-obvious reason.

According to the manual, "In the CAS, MAXREAL=1.79769313486*10^308"

Here are some interesting results that may help someone (Tim, Joe, anybody...) better understand what's going on:

0..9 Error: Invalid input
0..8.9 6.1469095538E303
0..8.92 7.13760485169E305
0..8.92025 7.60793580705E305

etc. tweaking the exponent until overflow...
0..8.920259874454 => 7.62587315929E305
0..8.920259874455 => +Inf

then looking for the next cliff...
0..8.921 +Inf
0..8.924 +Inf
0..8.925 +Inf
0..8.93 +Inf
0..8.935 +Inf
0..8.94 Error: Invalid input
0..8.95 Error: Invalid input

Definitely looks like the CAS is somehow being used here...