HP15c CE: 8x8 equation system

[J-F Garnier]

I did something similar some time ago as a simple test case for using multiple matrices beyond 64 registers and solving 8x8 systems on extended 15C platforms (but not the CE of course).
I built the test in such a way that the result can be verified.

Here are the details:

- Ensure your platform has 74 or more free ("uncommitted") registers.

- create and fill a 8x8 matrix A:

8  ENTER  DIM A
MATRIX 1
PI  STO RAN#
Set USER ON
enter and run this program:
001-42,21,11  LBL A
002-    42 36  RAN#
003-          1
004-          0
005-         20  *
006-     43 44  INT
007u     44 11  STO A
008-     22 11  GTO A

After the program terminates, the stack must be x=7, y=7, z=4, t=4.
Check that the first elements A are correct:
(USER is ON)
MATRIX 1
RCL A --> A(1,1)=8
RCL A --> A(1,2)=2
RCL A --> A(1,2)=0
...
then check A globally by calculating the norm (matrix 8):
RCL MATRIX A
MATRIX 8
--> 43.6921

- create and fill a 8x1 vector b

8  ENTER  1  DIM b
(USER is ON)
MATRIX 1
132  STO b
157  STO b
196  STO b
149  STO b
231  STO b
239  STO b
180  STO b
151  STO b

check that b is correct by calculating the norm (matrix 8):
RCL MATRIX b
MATRIX 8
--> 518.0473

- Now solve A.X=b, result in b:

RESULT b
RCL MATRIX b
RCL MATRIX A
/

- Check the solution is [ 1 2 3 4 5 6 7 8 ]

MATRIX 1
(USER is ON)
RCL b  --> b(1,1)=1
RCL b  --> b(2,1)=2
RCL b  --> b(3,1)=3
...
RCL b  --> b(8,1)=8

- Successfully tested on:

DM15L w/ 228 registers,
15C LE w/ 192 registers,
PX15C w/ 160 registers,
all with a standard partition 19 DIM (i)

J-F