Little problem(s) July 2022

[Thomas Klemm]

This is my attempt of a solution for #2 for the HP-42S:

Code:

00 { 41-Byte Prgm }
01▸LBL "FIND"
02 RCL- ST Y
03 STO "N"
04 INDEX "N"
05 R↓
06 EDIT
07▸LBL 00
08 [FIND]
09 XEQ 01
10 →
11 FC? 77
12 GTO 00
13 EXITALL
14 R↓
15 RTN
16▸LBL 01
17 RCLIJ
18 R↓
19 X<>Y
20 END

I tried to use the undocumented function [FIND] with John's idea.

Example

[ 4x1 Matrix ]
17
XEQ "FIND"

But alas it fails when using the Free42 simulator.
It appears that [FIND] is not using the indexed matrix N but the matrix that is currently edited.
Therefore all elements are found.

I've tried to index the matrix N within the loop but that gives me an error: Restricted Operation
Interestingly I can do that manually while editing the matrix.
But that exits the edit mode.

I can't check this with my HP-42S right now.
But maybe someone else can confirm that this is the same behaviour.