Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries/ --ompython_omhome=/usr Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.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/Buildings 8.1.4-maint.8.1.x/package.mo", uses=false)
Using package Buildings with version 8.1.4 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 8.1.4-maint.8.1.x/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: "" <> buildModelFMU(Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow,fileNamePrefix="Buildings_8_Buildings_ThermalZones_Detailed_Examples_Controls_Validation_ElectrochromicWindow",fmuType="me",version="2.0",platforms={"static"})
"" <> buildModelFMU(Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow,fileNamePrefix="Buildings_8_Buildings_ThermalZones_Detailed_Examples_Controls_Validation_ElectrochromicWindow",fmuType="me",version="2.0",platforms={"static"})
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.001805/0.001804, allocations: 99.62 kB / 15.05 MB, free: 1.105 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.003039/0.003038, allocations: 177.3 kB / 15.95 MB, free: 216 kB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 3.2.3+maint.om/package.mo): time 3.203/3.203, allocations: 205.4 MB / 222.1 MB, free: 5.66 MB / 174.1 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 8.1.4-maint.8.1.x/package.mo): time 3.127/3.127, allocations: 292.6 MB / 0.5497 GB, free: 14.59 MB / 462.1 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: Performance of FrontEnd - loaded program: time 0.001182/0.001182, allocations: 12.91 kB / 0.6737 GB, free: 26.26 MB / 0.5294 GB
Notification: Performance of FrontEnd - Absyn->SCode: time 0.5172/0.5184, allocations: 116.3 MB / 0.7872 GB, free: 11.86 MB / 0.6075 GB
Notification: Performance of NFInst.instantiate(Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow): time 0.004885/0.5234, allocations: 1.654 MB / 0.7889 GB, free: 10.2 MB / 0.6075 GB
Notification: Performance of NFInst.instExpressions: time 0.002471/0.5259, allocations: 0.6365 MB / 0.7895 GB, free: 9.551 MB / 0.6075 GB
Notification: Performance of NFInst.updateImplicitVariability: time 0.0002953/0.5263, allocations: 3.938 kB / 0.7895 GB, free: 9.547 MB / 0.6075 GB
Notification: Performance of NFTyping.typeComponents: time 9.044e-05/0.5264, allocations: 11.92 kB / 0.7895 GB, free: 9.535 MB / 0.6075 GB
Notification: Performance of NFTyping.typeBindings: time 0.0003891/0.5268, allocations: 47.83 kB / 0.7895 GB, free: 9.488 MB / 0.6075 GB
Notification: Performance of NFTyping.typeClassSections: time 0.0008607/0.5277, allocations: 119.3 kB / 0.7896 GB, free: 9.375 MB / 0.6075 GB
Notification: Performance of NFFlatten.flatten: time 0.0006379/0.5284, allocations: 163.7 kB / 0.7898 GB, free: 9.215 MB / 0.6075 GB
Notification: Performance of NFFlatten.resolveConnections: time 0.0003036/0.5287, allocations: 48.47 kB / 0.7899 GB, free: 9.164 MB / 0.6075 GB
Notification: Performance of NFEvalConstants.evaluate: time 0.000341/0.5291, allocations: 87.67 kB / 0.7899 GB, free: 9.078 MB / 0.6075 GB
Notification: Performance of NFSimplifyModel.simplify: time 0.0003257/0.5294, allocations: 103.6 kB / 0.79 GB, free: 8.977 MB / 0.6075 GB
Notification: Performance of NFPackage.collectConstants: time 9.422e-05/0.5295, allocations: 12 kB / 0.79 GB, free: 8.965 MB / 0.6075 GB
Notification: Performance of NFFlatten.collectFunctions: time 7.124e-05/0.5296, allocations: 8 kB / 0.7901 GB, free: 8.957 MB / 0.6075 GB
Notification: Performance of NFScalarize.scalarize: time 9.967e-05/0.5297, allocations: 39.88 kB / 0.7901 GB, free: 8.918 MB / 0.6075 GB
Notification: Performance of NFVerifyModel.verify: time 0.0001526/0.5299, allocations: 57.58 kB / 0.7901 GB, free: 8.855 MB / 0.6075 GB
Notification: Performance of NFConvertDAE.convert: time 0.000406/0.5303, allocations: 183.7 kB / 0.7903 GB, free: 8.676 MB / 0.6075 GB
Notification: Performance of FrontEnd - DAE generated: time 5.09e-06/0.5303, allocations: 0 / 0.7903 GB, free: 8.676 MB / 0.6075 GB
Notification: Performance of FrontEnd: time 2.464e-06/0.5303, allocations: 4 kB / 0.7903 GB, free: 8.672 MB / 0.6075 GB
Notification: Performance of Transformations before backend: time 1.68e-05/0.5304, allocations: 0 / 0.7903 GB, free: 8.672 MB / 0.6075 GB
Notification: Model statistics after passing the front-end and creating the data structures used by the back-end:
 * Number of equations: 30
 * Number of variables: 30
Notification: Performance of Generate backend data structure: time 0.002488/0.5329, allocations: 0.619 MB / 0.7909 GB, free: 7.992 MB / 0.6075 GB
Notification: Performance of prepare preOptimizeDAE: time 8.625e-05/0.533, allocations: 8.031 kB / 0.7909 GB, free: 7.984 MB / 0.6075 GB
Notification: Performance of preOpt introduceOutputAliases (simulation): time 0.0001778/0.5332, allocations: 50.55 kB / 0.791 GB, free: 7.926 MB / 0.6075 GB
Notification: Performance of preOpt normalInlineFunction (simulation): time 0.0001861/0.5334, allocations: 31.66 kB / 0.791 GB, free: 7.895 MB / 0.6075 GB
Notification: Performance of preOpt evaluateParameters (simulation): time 0.001013/0.5344, allocations: 275.5 kB / 0.7913 GB, free: 7.582 MB / 0.6075 GB
Notification: Performance of preOpt simplifyIfEquations (simulation): time 3.819e-05/0.5345, allocations: 8 kB / 0.7913 GB, free: 7.574 MB / 0.6075 GB
Notification: Performance of preOpt expandDerOperator (simulation): time 7.016e-05/0.5345, allocations: 23.92 kB / 0.7913 GB, free: 7.551 MB / 0.6075 GB
Notification: Performance of preOpt clockPartitioning (simulation): time 0.00137/0.5359, allocations: 256.1 kB / 0.7916 GB, free: 7.285 MB / 0.6075 GB
Notification: Performance of preOpt findStateOrder (simulation): time 1.664e-05/0.536, allocations: 4 kB / 0.7916 GB, free: 7.281 MB / 0.6075 GB
Notification: Performance of preOpt replaceEdgeChange (simulation): time 5.414e-05/0.536, allocations: 8 kB / 0.7916 GB, free: 7.273 MB / 0.6075 GB
Notification: Performance of preOpt inlineArrayEqn (simulation): time 1.359e-05/0.5361, allocations: 0 / 0.7916 GB, free: 7.273 MB / 0.6075 GB
Notification: Performance of preOpt removeEqualRHS (simulation): time 0.001799/0.5379, allocations: 271.8 kB / 0.7918 GB, free: 7.008 MB / 0.6075 GB
Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.001573/0.5395, allocations: 0.5312 MB / 0.7923 GB, free: 6.426 MB / 0.6075 GB
Notification: Performance of preOpt comSubExp (simulation): time 0.001929/0.5414, allocations: 318.5 kB / 0.7926 GB, free: 6.105 MB / 0.6075 GB
Notification: Performance of preOpt evalFunc (simulation): time 5.102e-05/0.5415, allocations: 4 kB / 0.7926 GB, free: 6.102 MB / 0.6075 GB
Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 0.001159/0.5427, allocations: 211.2 kB / 0.7929 GB, free: 5.883 MB / 0.6075 GB
Notification: Performance of pre-optimization done (n=15): time 7.845e-06/0.5427, allocations: 0 / 0.7929 GB, free: 5.883 MB / 0.6075 GB
Notification: Performance of matching and sorting (n=15): time 0.002909/0.5456, allocations: 459.8 kB / 0.7933 GB, free: 5.43 MB / 0.6075 GB
Notification: Performance of inlineWhenForInitialization (initialization): time 0.0001352/0.5458, allocations: 55.41 kB / 0.7933 GB, free: 5.363 MB / 0.6075 GB
Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.0006103/0.5464, allocations: 219.1 kB / 0.7936 GB, free: 5.137 MB / 0.6075 GB
Notification: Performance of collectPreVariables (initialization): time 8.333e-05/0.5465, allocations: 29.7 kB / 0.7936 GB, free: 5.102 MB / 0.6075 GB
Notification: Performance of collectInitialEqns (initialization): time 0.0002542/0.5468, allocations: 136.3 kB / 0.7937 GB, free: 4.961 MB / 0.6075 GB
Notification: Performance of collectInitialBindings (initialization): time 0.0001126/0.5469, allocations: 39.45 kB / 0.7937 GB, free: 4.922 MB / 0.6075 GB
Notification: Performance of simplifyInitialFunctions (initialization): time 2.22e-05/0.5469, allocations: 0 / 0.7937 GB, free: 4.922 MB / 0.6075 GB
Notification: Performance of setup shared object (initialization): time 0.0003342/0.5473, allocations: 330.8 kB / 0.7941 GB, free: 4.59 MB / 0.6075 GB
Notification: Performance of preBalanceInitialSystem (initialization): time 0.0007945/0.5481, allocations: 151.8 kB / 0.7942 GB, free: 4.441 MB / 0.6075 GB
Notification: Performance of partitionIndependentBlocks (initialization): time 0.0007503/0.5489, allocations: 139.8 kB / 0.7943 GB, free: 4.305 MB / 0.6075 GB
Notification: Performance of analyzeInitialSystem (initialization): time 0.0007958/0.5497, allocations: 175.3 kB / 0.7945 GB, free: 4.121 MB / 0.6075 GB
Notification: Performance of solveInitialSystemEqSystem (initialization): time 5.079e-06/0.5497, allocations: 0 / 0.7945 GB, free: 4.121 MB / 0.6075 GB
Notification: Performance of matching and sorting (n=19) (initialization): time 0.002021/0.5517, allocations: 411.4 kB / 0.7949 GB, free: 3.703 MB / 0.6075 GB
Notification: Performance of prepare postOptimizeDAE: time 0.0002773/0.552, allocations: 149.2 kB / 0.795 GB, free: 3.539 MB / 0.6075 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 1.871e-05/0.5521, allocations: 3.984 kB / 0.795 GB, free: 3.535 MB / 0.6075 GB
Notification: Performance of postOpt tearingSystem (initialization): time 3.795e-05/0.5521, allocations: 0 / 0.795 GB, free: 3.535 MB / 0.6075 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0004809/0.5526, allocations: 59.95 kB / 0.7951 GB, free: 3.477 MB / 0.6075 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 3.289e-05/0.5527, allocations: 11.92 kB / 0.7951 GB, free: 3.465 MB / 0.6075 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0005213/0.5532, allocations: 59.73 kB / 0.7952 GB, free: 3.406 MB / 0.6075 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 4.295e-05/0.5533, allocations: 4 kB / 0.7952 GB, free: 3.402 MB / 0.6075 GB
Notification: Performance of prepare postOptimizeDAE: time 2.083e-05/0.5533, allocations: 8 kB / 0.7952 GB, free: 3.395 MB / 0.6075 GB
Notification: Performance of postOpt replaceHomotopyWithSimplified (initialization): time 0.001522/0.5548, allocations: 367.1 kB / 0.7955 GB, free: 3.023 MB / 0.6075 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 4.909e-06/0.5549, allocations: 0 / 0.7955 GB, free: 3.023 MB / 0.6075 GB
Notification: Performance of postOpt tearingSystem (initialization): time 7.474e-06/0.5549, allocations: 0 / 0.7955 GB, free: 3.023 MB / 0.6075 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0003609/0.5553, allocations: 51.95 kB / 0.7956 GB, free: 2.973 MB / 0.6075 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 6.242e-06/0.5553, allocations: 4 kB / 0.7956 GB, free: 2.969 MB / 0.6075 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0004705/0.5558, allocations: 51.86 kB / 0.7956 GB, free: 2.918 MB / 0.6075 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 3.4e-05/0.5558, allocations: 7.938 kB / 0.7956 GB, free: 2.91 MB / 0.6075 GB
Notification: Model statistics after passing the back-end for initialization:
 * Number of independent subsystems: 1
 * Number of states: 0 ()
 * Number of discrete variables: 10 ($whenCondition2,$whenCondition1,$PRE.TMea.T_start,TMea.T_start,$PRE.TMea.count,TMea.count,$PRE.HMea.T_start,HMea.T_start,$PRE.HMea.count,HMea.count)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for initialization (17):
 * Single equations (assignments): 15
 * Array equations: 0
 * Algorithm blocks: 2
 * Record equations: 0
 * When equations: 0
 * If-equations: 0
 * Equation systems (linear and non-linear blocks): 0
 * Torn equation systems: 0
 * Mixed (continuous/discrete) equation systems: 0
Notification: Performance of prepare postOptimizeDAE: time 0.0003512/0.5562, allocations: 221 kB / 0.7959 GB, free: 2.684 MB / 0.6075 GB
Notification: Performance of postOpt lateInlineFunction (simulation): time 8.716e-05/0.5563, allocations: 19.72 kB / 0.7959 GB, free: 2.664 MB / 0.6075 GB
Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.0001306/0.5564, allocations: 21.53 kB / 0.7959 GB, free: 2.648 MB / 0.6075 GB
Notification: Performance of postOpt inlineArrayEqn (simulation): time 1.385e-05/0.5564, allocations: 7.984 kB / 0.7959 GB, free: 2.641 MB / 0.6075 GB
Notification: Performance of postOpt constantLinearSystem (simulation): time 1.199e-05/0.5565, allocations: 0 / 0.7959 GB, free: 2.641 MB / 0.6075 GB
Notification: Performance of postOpt simplifysemiLinear (simulation): time 6.822e-06/0.5565, allocations: 0 / 0.7959 GB, free: 2.641 MB / 0.6075 GB
Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.0005879/0.5571, allocations: 269.5 kB / 0.7962 GB, free: 2.328 MB / 0.6075 GB
Notification: Performance of postOpt simplifyComplexFunction (simulation): time 6.492e-06/0.5571, allocations: 0 / 0.7962 GB, free: 2.328 MB / 0.6075 GB
Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.000441/0.5575, allocations: 63.94 kB / 0.7962 GB, free: 2.266 MB / 0.6075 GB
Notification: Performance of postOpt tearingSystem (simulation): time 1.001e-05/0.5576, allocations: 0 / 0.7962 GB, free: 2.266 MB / 0.6075 GB
Notification: Performance of postOpt inputDerivativesUsed (simulation): time 4.809e-05/0.5576, allocations: 8 kB / 0.7962 GB, free: 2.258 MB / 0.6075 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 4.669e-06/0.5576, allocations: 3.938 kB / 0.7962 GB, free: 2.254 MB / 0.6075 GB
Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 3.947e-06/0.5576, allocations: 0 / 0.7962 GB, free: 2.254 MB / 0.6075 GB
Notification: Performance of postOpt symbolicJacobian (simulation): time 0.001816/0.5595, allocations: 356.6 kB / 0.7966 GB, free: 1.887 MB / 0.6075 GB
Notification: Performance of postOpt removeConstants (simulation): time 0.0001667/0.5597, allocations: 104.8 kB / 0.7967 GB, free: 1.766 MB / 0.6075 GB
Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 7.332e-05/0.5597, allocations: 3.984 kB / 0.7967 GB, free: 1.762 MB / 0.6075 GB
Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.0005319/0.5603, allocations: 51.95 kB / 0.7967 GB, free: 1.711 MB / 0.6075 GB
Notification: Performance of postOpt findZeroCrossings (simulation): time 0.0001821/0.5605, allocations: 27.95 kB / 0.7968 GB, free: 1.684 MB / 0.6075 GB
Notification: Performance of postOpt collapseArrayExpressions (simulation): time 3.541e-05/0.5605, allocations: 11.92 kB / 0.7968 GB, free: 1.672 MB / 0.6075 GB
Notification: Performance of sorting global known variables: time 0.000303/0.5609, allocations: 156.6 kB / 0.7969 GB, free: 1.52 MB / 0.6075 GB
Notification: Performance of sort global known variables: time 3.21e-07/0.5609, allocations: 0 / 0.7969 GB, free: 1.52 MB / 0.6075 GB
Notification: Performance of remove unused functions: time 0.0007334/0.5616, allocations: 71.84 kB / 0.797 GB, free: 1.449 MB / 0.6075 GB
Notification: Model statistics after passing the back-end for simulation:
 * Number of independent subsystems: 1
 * Number of states: 0 ()
 * Number of discrete variables: 6 ($whenCondition2,$whenCondition1,TMea.T_start,TMea.count,HMea.T_start,HMea.count)
 * Number of discrete states: 2 (TMea.count,HMea.count)
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for simulation (15):
 * Single equations (assignments): 11
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 0
 * When equations: 4
 * If-equations: 0
 * Equation systems (linear and non-linear blocks): 0
 * Torn equation systems: 0
 * Mixed (continuous/discrete) equation systems: 0
Notification: Performance of Backend phase and start with SimCode phase: time 0.002651/0.5643, allocations: 0.9035 MB / 0.7979 GB, free: 0.5156 MB / 0.6075 GB
Notification: Performance of simCode: created initialization part: time 0.003171/0.5675, allocations: 0.6535 MB / 0.7985 GB, free: 15.81 MB / 0.6231 GB
Notification: Performance of simCode: created event and clocks part: time 6.402e-06/0.5675, allocations: 0 / 0.7985 GB, free: 15.81 MB / 0.6231 GB
Notification: Performance of simCode: created simulation system equations: time 0.0009796/0.5685, allocations: 155.8 kB / 0.7986 GB, free: 15.66 MB / 0.6231 GB
Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.0006691/0.5692, allocations: 43.02 kB / 0.7987 GB, free: 15.62 MB / 0.6231 GB
Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.006423/0.5757, allocations: 1.428 MB / 0.8001 GB, free: 14.15 MB / 0.6231 GB
Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0006161/0.5764, allocations: 0.7367 MB / 0.8008 GB, free: 13.39 MB / 0.6231 GB
Notification: Performance of simCode: alias equations: time 0.0003141/0.5767, allocations: 25.55 kB / 0.8008 GB, free: 13.36 MB / 0.6231 GB
Notification: Performance of simCode: all other stuff during SimCode phase: time 0.0002481/0.577, allocations: 59.41 kB / 0.8009 GB, free: 13.31 MB / 0.6231 GB
Notification: Performance of SimCode: time 2.234e-06/0.577, allocations: 0 / 0.8009 GB, free: 13.31 MB / 0.6231 GB
Notification: Performance of buildModelFMU: Generate the FMI files: time 0.04377/0.6208, allocations: 4.631 MB / 0.8054 GB, free: 8.887 MB / 0.6231 GB
Notification: Performance of buildModelFMU: configured platform static using cached values: time 0.000581/0.6215, allocations: 216.9 kB / 0.8056 GB, free: 8.645 MB / 0.6231 GB
Notification: Performance of buildModelFMU: Generate platform static: time 3.491/4.113, allocations: 3.516 kB / 0.8056 GB, free: 8.645 MB / 0.6231 GB
(rm -f Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.pipe ; mkfifo Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.pipe ; head -c 1048576 < Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.pipe >> ../files/Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.sim & /home/hudson/saved_omc/OMSimulator/install/linux/bin/OMSimulator  --tempDir=temp_Buildings_8_Buildings_ThermalZones_Detailed_Examples_Controls_Validation_ElectrochromicWindow_fmu --startTime=0 --stopTime=172800 --timeout=50 --tolerance=1e-06 Buildings_8_Buildings_ThermalZones_Detailed_Examples_Controls_Validation_ElectrochromicWindow.fmu > Buildings_8_Buildings.ThermalZones.Detailed.Examples.Controls.Validation.ElectrochromicWindow.pipe 2>&1)
Environment - environmentSimulation: