Hello fellow Simulators,
i wanted to ask you what the numbers in my output mean. I am a little confused in decrypting what it means.
Mostly what i dont understand is the variable "nrm". Also when you see in my log file the numbers that kind of repeat themselves.
For example 10 0.7514E+00 etc.
If you have a clue, let me know.
Thank you,
domcivocato
StatCurrentSolver: ------------------------------------------------
StatCurrentSolver: Solving static current conduction solver
StatCurrentSolverBulkAssembly: Elapsed REAL time: 0.0779 (s)
StatCurrentSolverBCAssembly: Elapsed REAL time: 0.0026 (s)
CRS_IncompleteLU: ILU(0) (Real), Performing Factorization:
CRS_IncompleteLU: ILU(0) (Real), NOF nonzeros: 49473
CRS_IncompleteLU: ILU(0) (Real), filling (%) : 100
CRS_IncompleteLU: ILU(0) (Real), Factorization ready at (s): 0.00
10 0.7514E+00
20 0.4667E+00
30 0.2966E+00
40 0.1546E+00
50 0.1174E+00
60 0.1010E+00
70 0.2172E+00
80 0.1123E+00
90 0.1352E+00
100 0.2056E+00
110 0.2311E+00
120 0.3243E+00
130 0.4547E+00
140 0.6345E+00
150 0.6753E+00
160 0.9078E+00
170 0.1077E+01
180 0.1010E+01
190 0.8410E+00
200 0.8324E+00
210 0.8051E+00
220 0.3766E+00
230 0.3817E+00
240 0.3720E+00
250 0.3660E+00
260 0.4157E+00
270 0.4478E+00
280 0.1279E+02
290 0.1471E+01
300 0.2861E+01
310 0.2783E+01
320 0.4185E+02
330 0.5257E+01
340 0.2888E+01
350 0.2737E+01
360 0.2365E+01
370 0.2394E+01
380 0.2201E+01
390 0.2503E+01
400 0.5770E+01
410 0.5320E+01
420 0.5224E+01
430 0.5260E+01
440 0.5682E+01
450 0.5841E+01
460 0.4841E+01
470 0.4971E+01
480 0.3135E+01
490 0.3263E+01
500 0.3249E+01
501 0.3249E+01
IterSolve: Linear iteration did not converge to tolerance
ComputeChange: NS (ITER=1) (NRM,RELC): ( 4874034.9 2.0000000 ) :: currentsolver
What does the output mean?
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What does the output mean?
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Re: What does the output mean?
Hello,
Looking at the end of the solver log, where the heat solver doesn't converge, these rows appear:
The solution doesn't converge. If you want help with convergence, post the geometry file, instructions on meshing, and the sif file.
Rich.
Looking at the end of the solver log, where the heat solver doesn't converge, these rows appear:
So NRM = Result Norm, and RELC = Relative ChangeIterSolve: Linear iteration did not converge to tolerance
ComputeChange: NS (ITER=2) (NRM,RELC): ( 0.38565092E+37 1.9979994 ) :: heat equation
HeatSolve: iter: 2 Assembly: (s) 0.14 0.28
HeatSolve: iter: 2 Solve: (s) 0.27 0.53
HeatSolve: Result Norm : 3.8565092019157088E+036
HeatSolve: Relative Change : 1.9979994462034139
The solution doesn't converge. If you want help with convergence, post the geometry file, instructions on meshing, and the sif file.
Rich.
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Re: What does the output mean?
Hello Rich,
thanks for your answer! Now i get the abbreviations.
Can you make sense of the values posted before? Like
480 0.3135E+01
490 0.3263E+01
500 0.3249E+01
501 0.3249E+01
This seems also like a time or iteration step measure for the convergence. But this deviates from the convergence that is depicted in the RELC.
Also the time or iteration step seems weird, because i didnt specify nothing in the range of 500. Do you maybe have a clue what this numbers stand for?
Cheers,
Dominik
thanks for your answer! Now i get the abbreviations.
Can you make sense of the values posted before? Like
480 0.3135E+01
490 0.3263E+01
500 0.3249E+01
501 0.3249E+01
This seems also like a time or iteration step measure for the convergence. But this deviates from the convergence that is depicted in the RELC.
Also the time or iteration step seems weird, because i didnt specify nothing in the range of 500. Do you maybe have a clue what this numbers stand for?
Cheers,
Dominik
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Re: What does the output mean?
The default iterative solver generated by the gui usually has something like this
Nonlinear System Convergence Tolerance = 1.0e-7
Nonlinear System Max Iterations = 20
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-3
Nonlinear System Relaxation Factor = 1
Linear System Solver = Iterative
Linear System Iterative Method = BiCGStab
Linear System Max Iterations = 500
Linear System Convergence Tolerance = 1.0e-10
the output
480 0.3135E+01
490 0.3263E+01
500 0.3249E+01
501 0.3249E+01
is from the linear solver and it goes until it hits the convergence tolerance
or the max iterations
The other output is from the non-linear solver, the code alternates between the linear solver and the non-linear solver until it converges on the steady state tolerance or it diverges.
Nonlinear System Convergence Tolerance = 1.0e-7
Nonlinear System Max Iterations = 20
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-3
Nonlinear System Relaxation Factor = 1
Linear System Solver = Iterative
Linear System Iterative Method = BiCGStab
Linear System Max Iterations = 500
Linear System Convergence Tolerance = 1.0e-10
the output
480 0.3135E+01
490 0.3263E+01
500 0.3249E+01
501 0.3249E+01
is from the linear solver and it goes until it hits the convergence tolerance
or the max iterations
The other output is from the non-linear solver, the code alternates between the linear solver and the non-linear solver until it converges on the steady state tolerance or it diverges.
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Re: What does the output mean?
Thanks for your answer, that makes sense!
Cheers,
Dominik
Cheers,
Dominik
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Re: What does the output mean?
Hi Dominik,
The 1st thing to get convergence here could be to change "ILU0" to "ILU1" or "ILU2". From linear solvers "BiCGtabl" and "idrs" are usually the most robust.
-Peter
The 1st thing to get convergence here could be to change "ILU0" to "ILU1" or "ILU2". From linear solvers "BiCGtabl" and "idrs" are usually the most robust.
-Peter
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Re: What does the output mean?
Okay thanks, that is very good to know.
Cheers,
Dominik
Cheers,
Dominik