Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries/ --ompython_omhome=/usr BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.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 4.0.0+maint.om/package.mo", uses=false) loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/NcDataReader2 2.5.1-master/package.mo", uses=false) loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/package.mo", uses=false) Using package BuildingSystems with version 2.0.0-beta (/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/package.mo) Using package NcDataReader2 with version 2.5.1 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/NcDataReader2 2.5.1-master/package.mo) Using package Modelica with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+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(BuildingSystems.Utilities.Math.Functions.Examples.Binomial,fileNamePrefix="BuildingSystems_BuildingSystems_Utilities_Math_Functions_Examples_Binomial",fmuType="me",version="2.0",platforms={"static"}) "" <> buildModelFMU(BuildingSystems.Utilities.Math.Functions.Examples.Binomial,fileNamePrefix="BuildingSystems_BuildingSystems_Utilities_Math_Functions_Examples_Binomial",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 0.0006895/0.0006898, allocations: 91.53 kB / 15.06 MB, free: 1.098 MB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.000972/0.0009721, allocations: 172.7 kB / 15.95 MB, free: 208 kB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.254/1.254, allocations: 223.3 MB / 240 MB, free: 5.352 MB / 190.1 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/NcDataReader2 2.5.1-master/package.mo): time 0.001579/0.001579, allocations: 274.1 kB / 291.3 MB, free: 1.906 MB / 238.1 MB [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:5:3-5:34:writable] Warning: Got element f_alp that was not referenced in the package.order file. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:6:3-6:35:writable] Warning: Elements in the package.mo-file need to be in the same relative order as the package.order file. Got element named f_lay but it was already added because it was not the next element in the list at that time. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:6:3-6:35:writable] Warning: Got element f_lay that was not referenced in the package.order file. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:7:3-7:37:writable] Warning: Elements in the package.mo-file need to be in the same relative order as the package.order file. Got element named f_loss but it was already added because it was not the next element in the list at that time. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:7:3-7:37:writable] Warning: Got element f_loss that was not referenced in the package.order file. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:8:3-8:33:writable] Warning: Elements in the package.mo-file need to be in the same relative order as the package.order file. Got element named f_pv but it was already added because it was not the next element in the list at that time. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:8:3-8:33:writable] Warning: Got element f_pv that was not referenced in the package.order file. [/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/Buildings/Airvolumes/Parameter/package.mo:2:1-34:14:writable] Warning: f_pv was referenced in the package.order file, but was not found in package.mo, f_pv/package.mo or f_pv.mo. Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/BuildingSystems 2.0.0-master/package.mo): time 0.804/0.804, allocations: 144.7 MB / 487.2 MB, free: 7.168 MB / 350.1 MB Notification: Performance of FrontEnd - loaded program: time 0.000401/0.000401, allocations: 14.75 kB / 0.5686 GB, free: 38.72 MB / 430.1 MB Notification: Performance of FrontEnd - Absyn->SCode: time 0.1539/0.1543, allocations: 83.09 MB / 0.6497 GB, free: 3.617 MB / 446.1 MB Notification: Performance of NFInst.instantiate(BuildingSystems.Utilities.Math.Functions.Examples.Binomial): time 0.0007861/0.1551, allocations: 311.7 kB / 0.65 GB, free: 3.312 MB / 446.1 MB Notification: Performance of NFInst.instExpressions: time 0.0003856/0.1556, allocations: 89.11 kB / 0.6501 GB, free: 3.227 MB / 446.1 MB Notification: Performance of NFInst.updateImplicitVariability: time 2.83e-05/0.1556, allocations: 0.6562 kB / 0.6501 GB, free: 3.227 MB / 446.1 MB Notification: Performance of NFTyping.typeComponents: time 2.634e-05/0.1556, allocations: 0.9688 kB / 0.6501 GB, free: 3.227 MB / 446.1 MB Notification: Performance of NFTyping.typeBindings: time 6.563e-06/0.1557, allocations: 0 / 0.6501 GB, free: 3.227 MB / 446.1 MB Notification: Performance of NFTyping.typeClassSections: time 0.00029/0.156, allocations: 35.89 kB / 0.6501 GB, free: 3.191 MB / 446.1 MB Notification: Performance of NFFlatten.flatten: time 0.0001221/0.1561, allocations: 56.62 kB / 0.6502 GB, free: 3.137 MB / 446.1 MB Notification: Performance of NFFlatten.resolveConnections: time 4.445e-05/0.1561, allocations: 0 / 0.6502 GB, free: 3.137 MB / 446.1 MB Notification: Performance of NFEvalConstants.evaluate: time 4.175e-05/0.1562, allocations: 28.97 kB / 0.6502 GB, free: 3.109 MB / 446.1 MB Notification: Performance of NFSimplifyModel.simplify: time 4.72e-05/0.1563, allocations: 19.97 kB / 0.6502 GB, free: 3.09 MB / 446.1 MB Notification: Performance of NFPackage.collectConstants: time 1.92e-05/0.1563, allocations: 4.5 kB / 0.6502 GB, free: 3.086 MB / 446.1 MB Notification: Performance of NFFlatten.collectFunctions: time 0.0001271/0.1564, allocations: 39.95 kB / 0.6503 GB, free: 3.047 MB / 446.1 MB Notification: Performance of NFScalarize.scalarize: time 3.376e-05/0.1565, allocations: 21.16 kB / 0.6503 GB, free: 3.027 MB / 446.1 MB Notification: Performance of NFVerifyModel.verify: time 3.699e-05/0.1565, allocations: 37.64 kB / 0.6503 GB, free: 2.984 MB / 446.1 MB Notification: Performance of NFConvertDAE.convert: time 0.000102/0.1566, allocations: 47.88 kB / 0.6504 GB, free: 2.938 MB / 446.1 MB Notification: Performance of FrontEnd - DAE generated: time 4.98e-06/0.1566, allocations: 1.688 kB / 0.6504 GB, free: 2.938 MB / 446.1 MB Notification: Performance of FrontEnd: time 1.483e-06/0.1566, allocations: 0 / 0.6504 GB, free: 2.938 MB / 446.1 MB Notification: Performance of Transformations before backend: time 4.188e-06/0.1566, allocations: 0 / 0.6504 GB, free: 2.938 MB / 446.1 MB Notification: Model statistics after passing the front-end and creating the data structures used by the back-end: * Number of equations: 11 * Number of variables: 11 Notification: Performance of Generate backend data structure: time 0.0004359/0.1571, allocations: 358.3 kB / 0.6507 GB, free: 2.543 MB / 446.1 MB Notification: Performance of prepare preOptimizeDAE: time 3.903e-05/0.1571, allocations: 8.031 kB / 0.6507 GB, free: 2.535 MB / 446.1 MB Notification: Performance of preOpt introduceOutputAliases (simulation): time 4.523e-05/0.1572, allocations: 46.55 kB / 0.6508 GB, free: 2.48 MB / 446.1 MB Notification: Performance of preOpt normalInlineFunction (simulation): time 2.944e-05/0.1572, allocations: 6.031 kB / 0.6508 GB, free: 2.477 MB / 446.1 MB Notification: Performance of preOpt evaluateParameters (simulation): time 9.522e-05/0.1573, allocations: 163.4 kB / 0.6509 GB, free: 2.277 MB / 446.1 MB Notification: Performance of preOpt simplifyIfEquations (simulation): time 0.0002662/0.1576, allocations: 285 kB / 0.6512 GB, free: 1.938 MB / 446.1 MB Notification: Performance of preOpt expandDerOperator (simulation): time 1.68e-05/0.1576, allocations: 4 kB / 0.6512 GB, free: 1.934 MB / 446.1 MB Notification: Performance of preOpt clockPartitioning (simulation): time 0.0002296/0.1578, allocations: 83.95 kB / 0.6513 GB, free: 1.848 MB / 446.1 MB Notification: Performance of preOpt findStateOrder (simulation): time 8.045e-06/0.1579, allocations: 0 / 0.6513 GB, free: 1.848 MB / 446.1 MB Notification: Performance of preOpt replaceEdgeChange (simulation): time 1.025e-05/0.1579, allocations: 0 / 0.6513 GB, free: 1.848 MB / 446.1 MB Notification: Performance of preOpt inlineArrayEqn (simulation): time 4.659e-06/0.1579, allocations: 0 / 0.6513 GB, free: 1.848 MB / 446.1 MB Notification: Performance of preOpt removeEqualRHS (simulation): time 0.0003299/0.1582, allocations: 135.8 kB / 0.6514 GB, free: 1.715 MB / 446.1 MB Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.0001824/0.1584, allocations: 177.6 kB / 0.6516 GB, free: 1.492 MB / 446.1 MB Notification: Performance of preOpt comSubExp (simulation): time 0.0002786/0.1587, allocations: 99.56 kB / 0.6517 GB, free: 1.387 MB / 446.1 MB Notification: Performance of preOpt resolveLoops (simulation): time 0.0001328/0.1588, allocations: 49.36 kB / 0.6517 GB, free: 1.336 MB / 446.1 MB Notification: Performance of preOpt evalFunc (simulation): time 2.636e-05/0.1589, allocations: 4.516 kB / 0.6517 GB, free: 1.332 MB / 446.1 MB Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 2.878e-05/0.1589, allocations: 39.19 kB / 0.6518 GB, free: 1.285 MB / 446.1 MB Notification: Performance of pre-optimization done (n=11): time 1.142e-06/0.1589, allocations: 1.219 kB / 0.6518 GB, free: 1.285 MB / 446.1 MB Notification: Performance of matching and sorting (n=11): time 0.0004859/0.1594, allocations: 145.8 kB / 0.6519 GB, free: 1.137 MB / 446.1 MB Notification: Performance of inlineWhenForInitialization (initialization): time 3.477e-05/0.1595, allocations: 52.84 kB / 0.652 GB, free: 1.074 MB / 446.1 MB Notification: Performance of selectInitializationVariablesDAE (initialization): time 4.337e-05/0.1595, allocations: 89.86 kB / 0.6521 GB, free: 0.9766 MB / 446.1 MB Notification: Performance of collectPreVariables (initialization): time 1.503e-05/0.1595, allocations: 29.7 kB / 0.6521 GB, free: 0.9414 MB / 446.1 MB Notification: Performance of collectInitialEqns (initialization): time 2.715e-05/0.1596, allocations: 85.3 kB / 0.6522 GB, free: 0.8516 MB / 446.1 MB Notification: Performance of collectInitialBindings (initialization): time 6.538e-05/0.1596, allocations: 35.45 kB / 0.6522 GB, free: 0.8164 MB / 446.1 MB Notification: Performance of simplifyInitialFunctions (initialization): time 6.052e-06/0.1596, allocations: 4.531 kB / 0.6522 GB, free: 0.8125 MB / 446.1 MB Notification: Performance of setup shared object (initialization): time 0.0001081/0.1598, allocations: 320.3 kB / 0.6525 GB, free: 0.4922 MB / 446.1 MB Notification: Performance of preBalanceInitialSystem (initialization): time 0.0001209/0.1599, allocations: 31.92 kB / 0.6525 GB, free: 472 kB / 446.1 MB Notification: Performance of partitionIndependentBlocks (initialization): time 0.0001179/0.16, allocations: 31.97 kB / 0.6526 GB, free: 440 kB / 446.1 MB Notification: Performance of analyzeInitialSystem (initialization): time 0.0001294/0.1601, allocations: 36.62 kB / 0.6526 GB, free: 404 kB / 446.1 MB Notification: Performance of solveInitialSystemEqSystem (initialization): time 1.823e-06/0.1602, allocations: 0.75 kB / 0.6526 GB, free: 404 kB / 446.1 MB Notification: Performance of matching and sorting (n=11) (initialization): time 0.0003074/0.1605, allocations: 109.6 kB / 0.6527 GB, free: 288 kB / 446.1 MB Notification: Performance of prepare postOptimizeDAE: time 1.776e-05/0.1605, allocations: 12.97 kB / 0.6527 GB, free: 276 kB / 446.1 MB Notification: Performance of postOpt simplifyComplexFunction (initialization): time 5.22e-06/0.1605, allocations: 0 / 0.6527 GB, free: 276 kB / 446.1 MB Notification: Performance of postOpt tearingSystem (initialization): time 1.282e-05/0.1605, allocations: 0 / 0.6527 GB, free: 276 kB / 446.1 MB Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0001383/0.1607, allocations: 25.52 kB / 0.6527 GB, free: 252 kB / 446.1 MB Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 8.496e-06/0.1607, allocations: 7.938 kB / 0.6528 GB, free: 244 kB / 446.1 MB Notification: Performance of postOpt simplifyAllExpressions (initialization): time 5.654e-05/0.1608, allocations: 11.91 kB / 0.6528 GB, free: 232 kB / 446.1 MB Notification: Performance of postOpt collapseArrayExpressions (initialization): time 1.388e-05/0.1608, allocations: 8.719 kB / 0.6528 GB, free: 224 kB / 446.1 MB Notification: Model statistics after passing the back-end for initialization: * Number of independent subsystems: 1 * Number of states: 0 () * Number of discrete variables: 1 (n) * Number of discrete states: 0 () * Number of clocked states: 0 () * Top-level inputs: 0 Notification: Strong component statistics for initialization (11): * Single equations (assignments): 11 * Array equations: 0 * Algorithm blocks: 0 * 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 9.278e-05/0.1609, allocations: 119.1 kB / 0.6529 GB, free: 96 kB / 446.1 MB Notification: Performance of postOpt lateInlineFunction (simulation): time 1.553e-05/0.1609, allocations: 11.86 kB / 0.6529 GB, free: 84 kB / 446.1 MB Notification: Performance of postOpt wrapFunctionCalls (simulation): time 3.727e-05/0.1609, allocations: 7.969 kB / 0.6529 GB, free: 76 kB / 446.1 MB Notification: Performance of postOpt inlineArrayEqn (simulation): time 2.114e-06/0.1609, allocations: 0.6562 kB / 0.6529 GB, free: 76 kB / 446.1 MB Notification: Performance of postOpt constantLinearSystem (simulation): time 4.989e-06/0.161, allocations: 0.5 kB / 0.6529 GB, free: 76 kB / 446.1 MB Notification: Performance of postOpt simplifysemiLinear (simulation): time 4.959e-06/0.161, allocations: 4 kB / 0.6529 GB, free: 72 kB / 446.1 MB Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.0001576/0.1611, allocations: 178.3 kB / 0.6531 GB, free: 15.85 MB / 462.1 MB Notification: Performance of postOpt simplifyComplexFunction (simulation): time 1.704e-06/0.1611, allocations: 0 / 0.6531 GB, free: 15.85 MB / 462.1 MB Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.0001148/0.1613, allocations: 28.84 kB / 0.6531 GB, free: 15.82 MB / 462.1 MB Notification: Performance of postOpt tearingSystem (simulation): time 3.075e-06/0.1613, allocations: 0 / 0.6531 GB, free: 15.82 MB / 462.1 MB Notification: Performance of postOpt inputDerivativesUsed (simulation): time 1.484e-05/0.1613, allocations: 8.547 kB / 0.6531 GB, free: 15.81 MB / 462.1 MB Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 2.054e-06/0.1613, allocations: 0 / 0.6531 GB, free: 15.81 MB / 462.1 MB Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 1.232e-06/0.1613, allocations: 1.969 kB / 0.6531 GB, free: 15.81 MB / 462.1 MB Notification: Performance of postOpt symbolicJacobian (simulation): time 0.0003373/0.1617, allocations: 148.8 kB / 0.6533 GB, free: 15.65 MB / 462.1 MB Notification: Performance of postOpt removeConstants (simulation): time 3.322e-05/0.1617, allocations: 81.8 kB / 0.6533 GB, free: 15.55 MB / 462.1 MB Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 1.572e-05/0.1617, allocations: 0 / 0.6533 GB, free: 15.55 MB / 462.1 MB Notification: Performance of postOpt simplifyAllExpressions (simulation): time 5.49e-05/0.1618, allocations: 12.81 kB / 0.6534 GB, free: 15.54 MB / 462.1 MB Notification: Performance of postOpt findZeroCrossings (simulation): time 5.093e-05/0.1618, allocations: 11.98 kB / 0.6534 GB, free: 15.53 MB / 462.1 MB Notification: Performance of postOpt collapseArrayExpressions (simulation): time 1.085e-05/0.1619, allocations: 8.734 kB / 0.6534 GB, free: 15.52 MB / 462.1 MB Notification: Performance of sorting global known variables: time 2.623e-05/0.1619, allocations: 77.66 kB / 0.6534 GB, free: 15.45 MB / 462.1 MB Notification: Performance of sort global known variables: time 9e-08/0.1619, allocations: 0 / 0.6534 GB, free: 15.45 MB / 462.1 MB Notification: Performance of remove unused functions: time 0.0002162/0.1621, allocations: 20 kB / 0.6535 GB, free: 15.43 MB / 462.1 MB Notification: Model statistics after passing the back-end for simulation: * Number of independent subsystems: 1 * Number of states: 0 () * Number of discrete variables: 1 (n) * Number of discrete states: 0 () * Number of clocked states: 0 () * Top-level inputs: 0 Notification: Strong component statistics for simulation (11): * Single equations (assignments): 11 * Array equations: 0 * Algorithm blocks: 0 * 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 Backend phase and start with SimCode phase: time 0.0006752/0.1628, allocations: 0.692 MB / 0.6541 GB, free: 14.71 MB / 462.1 MB Notification: Performance of simCode: created initialization part: time 0.0003245/0.1631, allocations: 84.58 kB / 0.6542 GB, free: 14.62 MB / 462.1 MB Notification: Performance of simCode: created event and clocks part: time 1.984e-06/0.1631, allocations: 0.625 kB / 0.6542 GB, free: 14.62 MB / 462.1 MB Notification: Performance of simCode: created simulation system equations: time 0.0001475/0.1633, allocations: 49.5 kB / 0.6543 GB, free: 14.58 MB / 462.1 MB Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.0001387/0.1634, allocations: 12.17 kB / 0.6543 GB, free: 14.57 MB / 462.1 MB Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.0004984/0.164, allocations: 209.8 kB / 0.6545 GB, free: 14.32 MB / 462.1 MB Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0002517/0.1642, allocations: 0.6873 MB / 0.6552 GB, free: 13.61 MB / 462.1 MB Notification: Performance of simCode: alias equations: time 0.0001538/0.1644, allocations: 41.89 kB / 0.6552 GB, free: 13.57 MB / 462.1 MB Notification: Performance of simCode: all other stuff during SimCode phase: time 4.98e-05/0.1644, allocations: 23.42 kB / 0.6552 GB, free: 13.55 MB / 462.1 MB Notification: Performance of SimCode: time 2.21e-07/0.1644, allocations: 0.5625 kB / 0.6552 GB, free: 13.55 MB / 462.1 MB Notification: Performance of buildModelFMU: Generate the FMI files: time 0.01212/0.1766, allocations: 1.773 MB / 0.6569 GB, free: 11.93 MB / 462.1 MB Notification: Performance of buildModelFMU: configured platform static using cached values: time 0.0003243/0.177, allocations: 200.6 kB / 0.6571 GB, free: 11.68 MB / 462.1 MB Notification: Performance of buildModelFMU: Generate platform static: time 1.662/1.839, allocations: 0 / 0.6571 GB, free: 11.68 MB / 462.1 MB (rm -f BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.pipe ; mkfifo BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.pipe ; head -c 1048576 < BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.pipe >> ../files/BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.sim & /home/hudson/saved_omc/OMSimulator/install/linux/bin/OMSimulator --tempDir=temp_BuildingSystems_BuildingSystems_Utilities_Math_Functions_Examples_Binomial_fmu --startTime=0 --stopTime=15.9 --timeout=50 --tolerance=1e-06 BuildingSystems_BuildingSystems_Utilities_Math_Functions_Examples_Binomial.fmu > BuildingSystems_BuildingSystems.Utilities.Math.Functions.Examples.Binomial.pipe 2>&1) Environment - environmentSimulation: