Need help debugging program on HP 35s

[mbrethen]

That was my first try at programming the 35s. I made some minor modifications to an existing program written by Mr. Hanson and used it along with the other program from Stefan, already mentioned, for some engineering classes I was taking at the time.

So, yeah, I'm still learning. After spending a week debugging this program I traced the errors to lines L091-L114.

Code:

L001 LBL "L"
L002 X<>Y
L003 .1
L004 %
L005 +
L006 STO N
L007 *
L008 LASTX
L009 FP
L010 -
L011 STO O
L012 1
L013 STO D       
L014 LASTX
L015 %
L016 REGZ
L017 IP
L018 +
L019 STO M
L020 FS? 1
L021 GTO L059
L022 IP
L023 RCL O
L024 FP
L025 +
L026 STO I
L027 0
L028 RCL(I)
L029 ABS 
L030 X<Y?
L031 GTO L036
L032 X<>Y
L033 CLX
L034 RCL I
L035 STO J
L036 RDN
L037 DSE I
L038 GTO L028
L039 RCL M
L040 STO I
L041 ENTER
L042 FP
L043 RCL J
L044 IP
L045 +
L046 STO J
L047 X=Y?
L048 GTO L059
L049 RCL(J)
L050 X<>(I)
L051 STO(J)
L052 DSE J
L053 RDN
L054 DSE I
L055 GTO L049
L056 RCL D
L057 +/-
L058 STO D
L059 CLX
L060 FS? 0
L061 GTO L063
L062 E-7
L063 RCL M
L064 STO I
L065 CLX
L066 RCL(I)
L067 STO* D
L068 ABS
L069 X<=Y?
L070 CLX
L071 X=0?
L072 STO D
L073 X=0?
L074 GTO L103
L075 LASTX
L076 ST/(I)
L077 DSE I
L078 GTO L076
L079 RCL O
L080 STO P
L081 RCL M
L082 STO I
L083 ENTER
L084 FP
L085 RCL P
L086 IP
L087 +
L088 X=Y?
L089 GTO L098
L090 STO J
L091 RCL(J)
L092 ENTER
L093 ENTER
L094 ENTER
L095 RCL*(I)
L096 STO-(J)
L097 DSE J
L098 RDN
L099 DSE I
L100 GTO L095
L101 DSE P
L102 GTO L081
L103 RCL O
L104 RCL- N
L105 STO O
L106 RCL M
L107 1
L108 -
L109 X>Y?
L110 GTO L114
L111 CLX
L112 RCL D
L113 RTN
L114 STO M
L115 DSE M
L116 RCL M
L117 GTO L020

I decided to replace those menu-driven programs with a library of matrix programs that use a control-number format similar to the 41 Advantage module.

So far, I have added the following to my library:
1. Storing a Matrix (which can be found here).
2. Addition & Subtraction
3. Multiplication
4. Norm of a Matrix
5. Trace of a Square Matrix
6. Transpose
a) General case
b) Square Matrix
7. Copying a Matrix

They are translations of Jean-Marc Baillard's programs for the 41.