HP49-HP50 : when {list of repeated solutions} —> {list with no rep. sol}

[DavidM]

(12-23-2022 11:57 PM)pier4r Wrote:  Is this sorcery? More seriously: is this documented anywhere in the official docs? (just to understand how one could discover it) Does it use '==' or SAME ? How is its speed?

Programming in System RPL by Eduardo M Kalinowski and Carsten Dominik is probably your best source of information for things like this.

SYSEVAL, LIBEVAL and FLASHEVAL are all UserRPL commands which allow an RPL program to execute code on the calculator that is normally only accessible to System RPL programs. Typos when entering the binary numbers used as input to these commands can wreak havoc with your calculator (including causing loss of data or corruption of random memory areas). The payoff, however, can be substantial for their use when managed appropriately.

The particular command that is executed using Joe's suggestion has a name: COMPRIMext. The description is simply:

Quote:( {} → {}' )
Suppress multiple occurrances (sic) in the list.

Generally speaking, SysRPL commands need very specific types of arguments. As long as you make sure that the needed arguments are present and are of the required type, you'll be fine.

In this particular case, the list elements are checked for binary equivalency. So in that respect its comparison is more like SAME than == if numbers are involved. Speed-wise you would likely find it to be faster than any "regular" User RPL code for performing the same non-sorted de-duplication. LDDUP from the ListExt library can be faster, though, especially for lists with 25 or more elements.