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Full Version: Oops! hp42s Mohr's Cicle Program
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I could not find a program written about Mohr's Circle on the hp42s.
So I did this for kicks!
HP 42s Program Mohr's
This simple program runs and find the principal stress using Mohr's circle equations. The example below solves for principal stress & normal stress.

Line Instruction
01 LBL "MOHR"
02 INPUT "1OR0"
03 x=0?
04 GTO "XYT"
05 INPUT "TAUXY"
06 INPUT "SIGX"
07 INPUT "SIGY"
08 +
09 2
10 ÷
11 STO "S"
12 RCL "SIGX"
13 RCL- "SIGY"
14 2
15 ÷
16 x|2
17 RCL "TAUXY"
18 x|2
19 +
20 SQRT
21 STO "R"
22 CLST
23 RCL "R"
24 RCL+ "S"
25 STO "SIG1"
26 RCL "S"
27 RCL- "R"
28 STO "SIG2"
29 VIEW "SIG1"
30 PSE
31 VIEW "SIG2"
32 PSE
33 RCL "SIGX"
34 RCL- "SIGY"
35 1/x
36 2
37 x
38 RCLx "TAUXY"
39 ATAN
40 2
41 ÷
42 STO "Q"
43 VIEW "Q"
44 PSE
45 VIEW "R"
46 PSE
47 STOP
48 LBL "XYT"
49 CLST
50 INPUT "Q"
51 INPUT "SIG1"
52 INPUT "SIG2"
53 -
54 2
55 ÷
56 STO "R"
57 VIEW "R"
58 PSE
59 +/-
60 RCL+ "SIG1"
61 STO "S"
62 VIEW "S"
63 PSE
64 RCL "Q"
65 2
66 x
67 COS
68 RCLx "R"
69 RCL- "S"
70 +/-
71 STO "SIGY"
72 RCL "S"
73 2
74 x
75 -
76 +/-
77 STO "SIGX"
78 RCL "Q"
79 2
80 x
81 TAN
82 RCL "SIGX"
83 RCL- "SIGY"
84 x
85 2
86 ÷
87 STO "TAUXY"
88 VIEW "SIGX"
89 PSE
90 VIEW "SIGY"
91 PSE
92 VIEW "TAUXY"
93 STOP
94 RTN

While writing the above I noticed a strange result which I narrowed down to codes.

Oops! this could be interesting, load this short program. I used the Free42 on my Palm T5. If you have the real thing give it a try.

01 LBL "OOPS"
02 CLST
03 STO "M"
04 STO "N"
05 INPUT "M"
06 INPUT "N"
07 -
08 x
09 2
10 ÷
11 STO "T"
12 VIEW "T"
10 RTN

Use the following values, M as 70,000 & N as -30,000
Strangely the Ans is T = 1,050,000,000 on the T5 version
Loaded the same program on the Android Free42 and the Ans is T = 30,002
Try it for yourself!
OOPS is giving me 1.05E9 on both versions I have on my iPhone. Check that you don't have some of the modernization options enabled on the Android version. I think there are some options that make the stack behave more like an RPL machine (at least in some builds/forks).
The same program on the HP 35s calculator gives me the correct answer T=0

01 LBL O
02 CLSTK
03 STO M
04 STO N
05 INPUT M
06 INPUT N
07 -
08 x
09 2
10 ÷
11 STO T
12 VIEW T
10 RTN

This must be a floating error in the Free42 app. I wonder if the actual HP 42s calculator gives T=0.

I had time to kill so I wrote one for the HP35s calculator too!

HP 35s Program Mohr's
This simple program runs and find the principal stress using Mohr's Circle. The examples below solves for principal stress & normal stress from angle.

Line Instruction
M001 LBL M
M002 SF 10
M003 MOHRS CIRC
M004 PSE
M006 PSE
M007 INPUT M
M008 x=0?
M009 GTO M060
M010 SOLV PRINCIP
M011 PSE
M012 INPUT T
M013 INPUT X
M014 INPUT Y
M015 +
M016 2
M017 ÷
M018 STO S
M019 RCL X
M020 RCL- Y
M021 2
M022 ÷
M023 x2
M024 RCL T
M025 x2
M026 +
M027 √x
M028 STO R
M029 CLSTK
M030 RCL R
M031 RCL+ S
M032 STO M
M033 RCL S
M034 RCL- R
M035 STO N
M036 SIGMA MAX
M037 PSE
M038 VIEW M
M039 SIGMA MIN
M040 PSE
M041 VIEW N
M042 RCL X
M043 RCL- Y
M044 1/x
M045 2
M046 x
M047 RCLx T
M048 ATAN
M049 2
M050 ÷
M051 STO Q
M052 ANGLE
M053 PSE
M054 VIEW Q
M055 T MAX
M056 PSE
M057 VIEW R
M058 GTO M112
M059 SF 10
M060 SOLVE X,Y,T
M061 PSE
M062 CLSTK
M063 ANGLE Q
M064 PSE
M065 INPUT Q
M066 SIGMA MAX
M067 PSE
M068 INPUT M
M069 SIGMA MIN
M070 PSE
M071 INPUT N
M072 -
M073 2
M074 ÷
M075 STO R
M076 T MAX
M077 PSE
M078 VIEW R
M079 +/-
M080 RCL+ M
M081 STO S
M083 PSE
M084 VIEW S
M085 RCL Q
M086 2
M087 x
M088 COS
M089 RCLx R
M090 RCL- S
M091 +/-
M092 STO Y
M093 RCL S
M094 2
M095 x
M096 -
M097 +/-
M098 STO X
M099 RCL Q
M100 2
M101 x
M102 TAN
M103 RCL X
M104 RCL- Y
M105 x
M106 2
M107 ÷
M108 STO T
M109 VIEW X
M110 VIEW Y
M111 VIEW T
M112 STOP
M113 RTN

shorter version of J. E. Charalambides HP 35s Mohr's Program.
Real physical 42S returns 1050000000, versions A & C.
INPUT on the 42S (and Free42) puts a 0 in the stack, so after the two INPUT statements your stack looks like:

Code:
```T: 0 Z: 70000 Y: 0 X: -30000```

Result is 1'050'000'000
So the Android version is wrong.
My Samsung S3 returns 1050000000.
Aha! that's what's happening, thank for the clarification. Correct me if I am wrong:-

CLST resets stack T Y X to zero
STO M stores 0 from stack
STO N stores 0
INPUT M brings back the M stored 0 before entering 70,000
INPUT N brings back the N stored 0 before entering -30,000

HP 35s calculator behaves differently the stored number will need a recall command first for this to happen. INPUT places the number on the stack, that's probably why T=0 in this case.

PS: Checked my android version again and got the same answer as the T5. Difference is only between 35s & 42s apparently. Maybe you can try other models Hp32sii 33s etc...
My Samsung Galaxy S4 running Free 42 1.5.5 returns
1,050,000,000

I also get the same result in Free42 Binary and Decimal 1.5.5 on windows.
The 41C doesn't have an INPUT command, so you don't have this problem there.

But you could do this:

Code:
```LBL "OOPS" "M?" PROMPT STO 00 "N?" PROMPT STO 01 - x 2 ÷ STO 02 VIEW 02 RTN```

...Which returns 0 if X is 0 when you run the program.
(06-02-2015 08:41 AM)Jean-Marc Wrote: [ -> ]Use the following values, M as 70,000 & N as -30,000
Strangely the Ans is T = 1,050,000,000 on the T5 version
Loaded the same program on the Android Free42 and the Ans is T = 30,002
Try it for yourself!

What Version number is the Android Free42 you're using?

I just tried it on Android Free42 Version 1.5.5 and get the 1,050,000,000 answer. That's on both my Nexus 7 and Moto X Phone.

Maybe your Android version is and older version?

Bill
Smithville, NJ
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