Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries/ --ompython_omhome=/usr Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.conf.json
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 3.2.3+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/Annex60 1.0.0/package.mo", uses=false)
Using package Annex60 with version 1.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Annex60 1.0.0/package.mo)
Using package Modelica with version 3.2.3 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 3.2.3+maint.om/package.mo)
Using package Complex with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo)
Using package ModelicaServices with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo)
Running command: translateModel(Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector,tolerance=1e-06,outputFormat="empty",numberOfIntervals=5000,variableFilter="",fileNamePrefix="Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector")
translateModel(Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector,tolerance=1e-06,outputFormat="empty",numberOfIntervals=5000,variableFilter="",fileNamePrefix="Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector")
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.0007923/0.0007921, allocations: 98.03 kB / 15.36 MB, free: 0.7344 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.00765/0.00765, allocations: 169.5 kB / 16.27 MB, free: 6.648 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 3.2.3+maint.om/package.mo): time 1.684/1.684, allocations: 205.4 MB / 222.4 MB, free: 5.562 MB / 174.1 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Annex60 1.0.0/package.mo): time 0.4666/0.4666, allocations: 55.01 MB / 325.7 MB, free: 0.5742 MB / 254.1 MB
Notification: Modelica requested package Complex of version 3.2.3. Complex 4.0.0 is used instead which states that it is fully compatible without conversion script needed.
Notification: Modelica requested package ModelicaServices of version 3.2.3. ModelicaServices 4.0.0 is used instead which states that it is fully compatible without conversion script needed.
Notification: Annex60 requested package Modelica of version 3.2.2. Modelica 3.2.3 is used instead which states that it is fully compatible without conversion script needed.
Notification: Performance of FrontEnd - loaded program: time 0.0005376/0.0005376, allocations: 12 kB / 397.3 MB, free: 11.34 MB / 334.1 MB
Notification: Performance of FrontEnd - Absyn->SCode: time 0.4346/0.4351, allocations: 60.72 MB / 458 MB, free: 38.35 MB / 382.1 MB
Notification: Performance of NFInst.instantiate(Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector): time 0.03479/0.4699, allocations: 40.5 MB / 498.5 MB, free: 12.66 MB / 382.1 MB
Notification: Performance of NFInst.instExpressions: time 0.01142/0.4814, allocations: 8.357 MB / 0.495 GB, free: 6.738 MB / 382.1 MB
Notification: Performance of NFInst.updateImplicitVariability: time 0.001819/0.4833, allocations: 32.34 kB / 0.495 GB, free: 6.727 MB / 382.1 MB
Notification: Performance of NFTyping.typeComponents: time 0.002312/0.4856, allocations: 0.5002 MB / 0.4955 GB, free: 6.449 MB / 382.1 MB
Notification: Performance of NFTyping.typeBindings: time 0.00496/0.4906, allocations: 1.155 MB / 0.4966 GB, free: 5.746 MB / 382.1 MB
Notification: Performance of NFTyping.typeClassSections: time 0.003642/0.4943, allocations: 0.9644 MB / 0.4976 GB, free: 5.195 MB / 382.1 MB
Notification: Performance of NFFlatten.flatten: time 0.005595/0.4999, allocations: 3.419 MB / 0.5009 GB, free: 3.887 MB / 382.1 MB
Notification: Performance of NFFlatten.resolveConnections: time 0.001833/0.5018, allocations: 0.7345 MB / 0.5016 GB, free: 3.582 MB / 382.1 MB
Notification: Performance of NFEvalConstants.evaluate: time 0.002827/0.5046, allocations: 0.8652 MB / 0.5025 GB, free: 3.199 MB / 382.1 MB
Notification: Performance of NFSimplifyModel.simplify: time 0.002398/0.507, allocations: 0.7341 MB / 0.5032 GB, free: 2.887 MB / 382.1 MB
Notification: Performance of NFPackage.collectConstants: time 0.0004169/0.5075, allocations: 39.22 kB / 0.5032 GB, free: 2.887 MB / 382.1 MB
Notification: Performance of NFFlatten.collectFunctions: time 0.003455/0.5109, allocations: 0.9823 MB / 0.5042 GB, free: 2.586 MB / 382.1 MB
Notification: Performance of NFScalarize.scalarize: time 0.0006897/0.5116, allocations: 260.2 kB / 0.5044 GB, free: 2.473 MB / 382.1 MB
Notification: Performance of NFVerifyModel.verify: time 0.002133/0.5138, allocations: 0.5869 MB / 0.505 GB, free: 2.105 MB / 382.1 MB
Notification: Performance of NFConvertDAE.convert: time 0.006511/0.5203, allocations: 2.228 MB / 0.5072 GB, free: 1.488 MB / 382.1 MB
Notification: Performance of FrontEnd - DAE generated: time 4.769e-06/0.5204, allocations: 0 / 0.5072 GB, free: 1.488 MB / 382.1 MB
Notification: Performance of FrontEnd: time 2.615e-06/0.5204, allocations: 0.6562 kB / 0.5072 GB, free: 1.488 MB / 382.1 MB
Notification: Performance of Transformations before backend: time 9.11e-05/0.5205, allocations: 1.469 kB / 0.5072 GB, free: 1.488 MB / 382.1 MB
Notification: Model statistics after passing the front-end and creating the data structures used by the back-end:
 * Number of equations: 171
 * Number of variables: 171
Notification: Performance of Generate backend data structure: time 0.005512/0.526, allocations: 1.52 MB / 0.5086 GB, free: 340 kB / 382.1 MB
Notification: Performance of prepare preOptimizeDAE: time 6.194e-05/0.5261, allocations: 8.938 kB / 0.5087 GB, free: 340 kB / 382.1 MB
Notification: Performance of preOpt normalInlineFunction (simulation): time 0.001242/0.5273, allocations: 139 kB / 0.5088 GB, free: 276 kB / 382.1 MB
Notification: Performance of preOpt evaluateParameters (simulation): time 0.00384/0.5312, allocations: 1.059 MB / 0.5098 GB, free: 15.59 MB / 398.1 MB
Notification: Performance of preOpt simplifyIfEquations (simulation): time 9.512e-05/0.5313, allocations: 52.25 kB / 0.5099 GB, free: 15.57 MB / 398.1 MB
Notification: Performance of preOpt expandDerOperator (simulation): time 0.0003461/0.5317, allocations: 76.03 kB / 0.5099 GB, free: 15.54 MB / 398.1 MB
Notification: Performance of preOpt clockPartitioning (simulation): time 0.002965/0.5347, allocations: 0.9721 MB / 0.5109 GB, free: 15.05 MB / 398.1 MB
Notification: Performance of preOpt findStateOrder (simulation): time 4.259e-05/0.5347, allocations: 5.344 kB / 0.5109 GB, free: 15.05 MB / 398.1 MB
Notification: Performance of preOpt replaceEdgeChange (simulation): time 0.0001185/0.5348, allocations: 29.12 kB / 0.5109 GB, free: 15.03 MB / 398.1 MB
Notification: Performance of preOpt inlineArrayEqn (simulation): time 5.315e-05/0.5349, allocations: 20.59 kB / 0.5109 GB, free: 15.03 MB / 398.1 MB
Notification: Performance of preOpt removeEqualRHS (simulation): time 0.002137/0.537, allocations: 0.7061 MB / 0.5116 GB, free: 14.78 MB / 398.1 MB
Warning: The model contains alias variables with redundant start and/or conflicting nominal values. It is recommended to resolve the conflicts, because otherwise the system could be hard to solve. To print the conflicting alias sets and the chosen candidates please use -d=aliasConflicts.
Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.008179/0.5452, allocations: 3.939 MB / 0.5155 GB, free: 11.83 MB / 398.1 MB
Notification: Performance of preOpt comSubExp (simulation): time 0.001671/0.547, allocations: 497.3 kB / 0.516 GB, free: 11.64 MB / 398.1 MB
Notification: Performance of preOpt resolveLoops (simulation): time 0.000791/0.5478, allocations: 303.6 kB / 0.5162 GB, free: 11.54 MB / 398.1 MB
Notification: Performance of preOpt evalFunc (simulation): time 0.0008841/0.5487, allocations: 464.2 kB / 0.5167 GB, free: 11.06 MB / 398.1 MB
Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 7.585e-05/0.5488, allocations: 42.16 kB / 0.5167 GB, free: 11.01 MB / 398.1 MB
Notification: Performance of pre-optimization done (n=38): time 4.689e-06/0.5488, allocations: 0 / 0.5167 GB, free: 11.01 MB / 398.1 MB
Notification: Performance of matching and sorting (n=40): time 0.007779/0.5566, allocations: 2.322 MB / 0.519 GB, free: 9.707 MB / 398.1 MB
Notification: Performance of inlineWhenForInitialization (initialization): time 0.0001593/0.5568, allocations: 193.3 kB / 0.5192 GB, free: 9.484 MB / 398.1 MB
Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.003046/0.5598, allocations: 1.11 MB / 0.5203 GB, free: 8.945 MB / 398.1 MB
Notification: Performance of collectPreVariables (initialization): time 9.977e-05/0.5599, allocations: 38.42 kB / 0.5203 GB, free: 8.906 MB / 398.1 MB
Notification: Performance of collectInitialEqns (initialization): time 0.0005849/0.5605, allocations: 499.1 kB / 0.5208 GB, free: 8.477 MB / 398.1 MB
Notification: Performance of collectInitialBindings (initialization): time 0.0001977/0.5607, allocations: 144.3 kB / 0.5209 GB, free: 8.352 MB / 398.1 MB
Notification: Performance of simplifyInitialFunctions (initialization): time 0.0001183/0.5609, allocations: 58.94 kB / 0.521 GB, free: 8.309 MB / 398.1 MB
Notification: Performance of setup shared object (initialization): time 0.0001366/0.561, allocations: 328.1 kB / 0.5213 GB, free: 7.988 MB / 398.1 MB
Notification: Performance of preBalanceInitialSystem (initialization): time 0.0007317/0.5617, allocations: 380 kB / 0.5216 GB, free: 7.816 MB / 398.1 MB
Notification: Performance of partitionIndependentBlocks (initialization): time 0.0009028/0.5627, allocations: 0.5326 MB / 0.5222 GB, free: 7.441 MB / 398.1 MB
Notification: Performance of analyzeInitialSystem (initialization): time 0.001717/0.5644, allocations: 1.09 MB / 0.5232 GB, free: 6.645 MB / 398.1 MB
Notification: Performance of solveInitialSystemEqSystem (initialization): time 6.983e-06/0.5644, allocations: 5.094 kB / 0.5232 GB, free: 6.641 MB / 398.1 MB
Notification: Performance of matching and sorting (n=73) (initialization): time 0.002331/0.5667, allocations: 1.208 MB / 0.5244 GB, free: 5.941 MB / 398.1 MB
Notification: Performance of prepare postOptimizeDAE: time 0.0002741/0.567, allocations: 372.8 kB / 0.5248 GB, free: 5.512 MB / 398.1 MB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 1.387e-05/0.5671, allocations: 4.438 kB / 0.5248 GB, free: 5.512 MB / 398.1 MB
Notification: Performance of postOpt tearingSystem (initialization): time 2.824e-05/0.5671, allocations: 6.875 kB / 0.5248 GB, free: 5.512 MB / 398.1 MB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0004796/0.5676, allocations: 121.2 kB / 0.5249 GB, free: 5.48 MB / 398.1 MB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 1.987e-05/0.5676, allocations: 16.31 kB / 0.5249 GB, free: 5.473 MB / 398.1 MB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.001093/0.5687, allocations: 85.14 kB / 0.525 GB, free: 5.434 MB / 398.1 MB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 9.029e-05/0.5688, allocations: 28.62 kB / 0.525 GB, free: 5.426 MB / 398.1 MB
Notification: Performance of prepare postOptimizeDAE: time 1.352e-05/0.5688, allocations: 8.062 kB / 0.525 GB, free: 5.422 MB / 398.1 MB
Notification: Performance of postOpt replaceHomotopyWithSimplified (initialization): time 0.002002/0.5708, allocations: 1.172 MB / 0.5262 GB, free: 4.746 MB / 398.1 MB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 8.446e-06/0.5709, allocations: 8.188 kB / 0.5262 GB, free: 4.742 MB / 398.1 MB
Notification: Performance of postOpt tearingSystem (initialization): time 1.301e-05/0.5709, allocations: 6.875 kB / 0.5262 GB, free: 4.742 MB / 398.1 MB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0003944/0.5713, allocations: 113.1 kB / 0.5263 GB, free: 4.715 MB / 398.1 MB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 1.355e-05/0.5713, allocations: 9.438 kB / 0.5263 GB, free: 4.711 MB / 398.1 MB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.001/0.5723, allocations: 68.44 kB / 0.5264 GB, free: 4.684 MB / 398.1 MB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 7.692e-05/0.5724, allocations: 24.81 kB / 0.5264 GB, free: 4.68 MB / 398.1 MB
Notification: Model statistics after passing the back-end for initialization:
 * Number of independent subsystems: 16
 * Number of states: 0 ()
 * Number of discrete variables: 3 (con.mod.airFlo_mod.i,con.mod.watFlo_mod.i,con.mod.temDif_mod.i)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for initialization (64):
 * Single equations (assignments): 58
 * Array equations: 0
 * Algorithm blocks: 6
 * Record equations: 0
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 0
 * Torn equation systems: 0
 * Mixed (continuous/discrete) equation systems: 0
Notification: Performance of prepare postOptimizeDAE: time 0.0007759/0.5732, allocations: 488.7 kB / 0.5269 GB, free: 4.262 MB / 398.1 MB
Notification: Performance of postOpt lateInlineFunction (simulation): time 0.0003143/0.5735, allocations: 114.4 kB / 0.527 GB, free: 4.199 MB / 398.1 MB
Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.001964/0.5755, allocations: 0.9655 MB / 0.5279 GB, free: 3.645 MB / 398.1 MB
Notification: Performance of postOpt inlineArrayEqn (simulation): time 1.763e-05/0.5755, allocations: 4.656 kB / 0.5279 GB, free: 3.645 MB / 398.1 MB
Notification: Performance of postOpt constantLinearSystem (simulation): time 5.67e-06/0.5755, allocations: 0 / 0.5279 GB, free: 3.645 MB / 398.1 MB
Notification: Performance of postOpt simplifysemiLinear (simulation): time 0.001444/0.577, allocations: 1.059 MB / 0.529 GB, free: 2.492 MB / 398.1 MB
Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.005644/0.5826, allocations: 2.263 MB / 0.5312 GB, free: 100 kB / 398.1 MB
Notification: Performance of postOpt simplifyComplexFunction (simulation): time 1.562e-05/0.5827, allocations: 4.406 kB / 0.5312 GB, free: 96 kB / 398.1 MB
Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.0005/0.5832, allocations: 83.89 kB / 0.5312 GB, free: 12 kB / 398.1 MB
Notification: Performance of postOpt tearingSystem (simulation): time 0.000274/0.5835, allocations: 40.91 kB / 0.5313 GB, free: 15.96 MB / 414.1 MB
Notification: Performance of postOpt inputDerivativesUsed (simulation): time 6.549e-05/0.5836, allocations: 20 kB / 0.5313 GB, free: 15.95 MB / 414.1 MB
Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.0006964/0.5843, allocations: 0.5835 MB / 0.5319 GB, free: 15.34 MB / 414.1 MB
Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 5.8e-06/0.5843, allocations: 8.062 kB / 0.5319 GB, free: 15.33 MB / 414.1 MB
Notification: Performance of postOpt symbolicJacobian (simulation): time 0.003815/0.5881, allocations: 1.533 MB / 0.5334 GB, free: 13.72 MB / 414.1 MB
Notification: Performance of postOpt removeConstants (simulation): time 0.0009929/0.5891, allocations: 295.7 kB / 0.5337 GB, free: 13.41 MB / 414.1 MB
Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 0.0004498/0.5896, allocations: 15.94 kB / 0.5337 GB, free: 13.39 MB / 414.1 MB
Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.001291/0.5909, allocations: 67.92 kB / 0.5337 GB, free: 13.33 MB / 414.1 MB
Notification: Performance of postOpt findZeroCrossings (simulation): time 0.0003014/0.5912, allocations: 55.91 kB / 0.5338 GB, free: 13.27 MB / 414.1 MB
Notification: Performance of postOpt collapseArrayExpressions (simulation): time 9.65e-05/0.5913, allocations: 19.98 kB / 0.5338 GB, free: 13.25 MB / 414.1 MB
Notification: Performance of sorting global known variables: time 0.002661/0.594, allocations: 0.7892 MB / 0.5346 GB, free: 12.46 MB / 414.1 MB
Notification: Performance of sort global known variables: time 2.505e-06/0.594, allocations: 4 kB / 0.5346 GB, free: 12.45 MB / 414.1 MB
Notification: Performance of remove unused functions: time 0.003733/0.5977, allocations: 487.8 kB / 0.5351 GB, free: 11.98 MB / 414.1 MB
Notification: Model statistics after passing the back-end for simulation:
 * Number of independent subsystems: 14
 * Number of states: 2 (con.hex.vol.dynBal.U,senTem.T)
 * Number of discrete variables: 3 (con.mod.temDif_mod.i,con.mod.watFlo_mod.i,con.mod.airFlo_mod.i)
 * Number of discrete states: 3 (con.mod.watFlo_mod.i,con.mod.airFlo_mod.i,con.mod.temDif_mod.i)
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for simulation (38):
 * Single equations (assignments): 32
 * Array equations: 0
 * Algorithm blocks: 3
 * Record equations: 2
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 0
 * Torn equation systems: 1
 * Mixed (continuous/discrete) equation systems: 0
Notification: Torn system details for strict tearing set:
 * Linear torn systems (#iteration vars, #inner vars, density): 0 systems
 * Non-linear torn systems (#iteration vars, #inner vars): 1 system
   {(1,3)}
Notification: Performance of Backend phase and start with SimCode phase: time 0.001624/0.5994, allocations: 334.9 kB / 0.5354 GB, free: 11.66 MB / 414.1 MB
Notification: Performance of simCode: created initialization part: time 0.00444/0.6038, allocations: 2.054 MB / 0.5374 GB, free: 9.457 MB / 414.1 MB
Notification: Performance of simCode: created event and clocks part: time 7.725e-06/0.6039, allocations: 0 / 0.5374 GB, free: 9.457 MB / 414.1 MB
Notification: Performance of simCode: created simulation system equations: time 0.001508/0.6054, allocations: 0.6009 MB / 0.538 GB, free: 8.82 MB / 414.1 MB
Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.006217/0.6116, allocations: 0.5509 MB / 0.5385 GB, free: 8.281 MB / 414.1 MB
Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.006915/0.6186, allocations: 2.43 MB / 0.5409 GB, free: 5.789 MB / 414.1 MB
Notification: Performance of simCode: some other stuff during SimCode phase: time 0.001657/0.6203, allocations: 1.084 MB / 0.5419 GB, free: 4.676 MB / 414.1 MB
Notification: Performance of simCode: alias equations: time 0.00196/0.6222, allocations: 213.4 kB / 0.5421 GB, free: 4.48 MB / 414.1 MB
Notification: Performance of simCode: all other stuff during SimCode phase: time 0.0004592/0.6227, allocations: 83.42 kB / 0.5422 GB, free: 4.398 MB / 414.1 MB
Notification: Performance of SimCode: time 8.41e-07/0.6227, allocations: 0 / 0.5422 GB, free: 4.398 MB / 414.1 MB
Notification: Performance of Templates: time 0.06349/0.6862, allocations: 24.3 MB / 0.5659 GB, free: 12.36 MB / 446.1 MB
make -j1 -f Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.makefile
Environment - environmentSimulation:
(rm -f Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.pipe ; mkfifo Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.pipe ; head -c 1048576 < Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.pipe >> ../files/Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.sim & ./Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector  -abortSlowSimulation -alarm=480 -lv LOG_STATS > Annex60_1.0.0_Annex60.Fluid.HeatExchangers.ActiveBeams.BaseClasses.Examples.Convector.pipe 2>&1)
Environment - environmentSimulation: