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I just tried the matrix inversion command with a simple 4x4 matrix. Calling M-1 directly from the keyboard makes the calculator shut down (!). Sometimes the VERS screen is displayed instead.
However, if the same M-1 command is used from within a program, everything works fine:
001 LBL A
002 M-1
003 END
Used this way, the command is executed as expected. The same applies to M
-1 calls from the library, e.g. the matrix editor MED.
All this applies to Version 3.1 3325 as well as the new 3.2 3350 (updated a few minutes ago). So, is it the firmware or is there a problem with my hardware?
Dieter
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Quote:
I just tried the matrix inversion command with a simple 4x4 matrix. Calling M-1 directly from the keyboard makes the calculator shut down (!). Sometimes the VERS screen is displayed instead.
Have you tried it on the emulator, too?
I just did it (also 4x4) and had no problems.
Franz
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The emulator works fine. It's "the real thing" that behaves that way.
Dieter
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Hmmh, I just tried with build 3335 on my "real thing" and everything worked fine.
My matrix (chose some arbitrary values without thinking much):
1 2 3 4
0 1 4 9
7 6 5 4
1 0 -1 1
How's your matrix looking?
d:-)
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Quote:
How's your matrix looking?
It's looking great, of course. 8-)
Since the early Eightes I'm using a simple test matrix, taken from a book on numerical algorithms I bought back then:
5 7 6 5 68 -41 -17 10
7 10 8 7 -41 25 10 -6
A = 6 8 10 9 Inverse = -17 10 5 -3
5 7 9 10 10 -6 -3 2
This, as well as a 4th...6th order Hilbert matrix, usually is the first thing I try with new matrix software.
But I do not think the matrix itself is the reason for this strange behaviour. I fear something went wrong with the crystal/IR upgrade and it's actually a hardware problem. The same BTW happens with the LINEQS command. I just wonder why everything is fine as soon as the same functions are called from within a program. Strange.
Dieter
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I fear you're right. Your matrix inverts on my calculator just fine. I can't tell you, however, how the quartz / IR shall effect your calculations - maybe Marcus knows more about that particular case?
d;-)
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Dieter, I suspect your hardware is broken. What does BATT say? Can you switch to SLOW mode and try again?
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BATT returns 2,9 V, and after SLOW the same thing happens: M-1 turns the device off, and in some cases it displays the VERS message.
Dieter
Edited: 5 Jan 2013, 5:33 p.m.
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M-1 and LINEQU function pretty much the same underneath. They both perform a Doolittle LU decomposition with partial pivoting and then solve the system of equations (many times for M-1).
I've no idea what is causing your problem :-(
- Pauli
Edited: 5 Jan 2013, 8:03 p.m.
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Dieter, have you tried re-flashing the 34s software?
John
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Yes, of course a firmware update was the first thing I tried. But the problem showed up with version 3.1 3325 as well as 3.2 3350. It seems to be a hardware problem.
Dieter