Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries --ompython_omhome=/usr ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.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/ModelicaTest 4.0.0+maint.om/package.mo", uses=false)
Using package ModelicaTest with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaTest 4.0.0+maint.om/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: translateModel(ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|volume.medium.T|volume.medium.p",fileNamePrefix="ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT")
translateModel(ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|volume.medium.T|volume.medium.p",fileNamePrefix="ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT")
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.001267/0.001267, allocations: 118.4 kB / 17.78 MB, free: 5.262 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.001516/0.001517, allocations: 183.8 kB / 18.71 MB, free: 4.34 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.386/1.386, allocations: 222.9 MB / 242.4 MB, free: 15.07 MB / 206.1 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaTest 4.0.0+maint.om/package.mo): time 0.2119/0.2119, allocations: 44.18 MB / 336.7 MB, free: 2.68 MB / 270.1 MB
Notification: Performance of FrontEnd - loaded program: time 0.001251/0.001251, allocations: 59.91 kB / 470.5 MB, free: 13.17 MB / 350.1 MB
Notification: Performance of FrontEnd - Absyn->SCode: time 0.3651/0.3664, allocations: 60.82 MB / 0.5189 GB, free: 3.613 MB / 382.1 MB
Notification: Performance of NFInst.instantiate(ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT): time 0.04141/0.4078, allocations: 39.04 MB / 0.557 GB, free: 4.934 MB / 414.1 MB
Notification: Performance of NFInst.instExpressions: time 0.02671/0.4346, allocations: 20.14 MB / 0.5767 GB, free: 0.7305 MB / 430.1 MB
Notification: Performance of NFInst.updateImplicitVariability: time 0.001251/0.4359, allocations: 19.88 kB / 0.5767 GB, free: 0.7109 MB / 430.1 MB
Notification: Performance of NFTyping.typeComponents: time 0.001606/0.4376, allocations: 453.3 kB / 0.5772 GB, free: 272 kB / 430.1 MB
Notification: Performance of NFTyping.typeBindings: time 0.01906/0.4567, allocations: 5.124 MB / 0.5822 GB, free: 11.14 MB / 446.1 MB
Notification: Performance of NFTyping.typeClassSections: time 0.01067/0.4674, allocations: 2.567 MB / 0.5847 GB, free: 8.574 MB / 446.1 MB
Notification: Performance of NFFlatten.flatten: time 0.004221/0.4716, allocations: 1.965 MB / 0.5866 GB, free: 6.598 MB / 446.1 MB
Notification: Performance of NFFlatten.resolveConnections: time 0.00131/0.473, allocations: 493.4 kB / 0.5871 GB, free: 6.102 MB / 446.1 MB
Notification: Performance of NFEvalConstants.evaluate: time 0.01648/0.4895, allocations: 4.156 MB / 0.5911 GB, free: 1.891 MB / 446.1 MB
Notification: Performance of NFSimplifyModel.simplify: time 0.01887/0.5084, allocations: 5.417 MB / 0.5964 GB, free: 12.38 MB / 462.1 MB
Notification: Performance of NFPackage.collectConstants: time 0.0002935/0.5087, allocations: 68 kB / 0.5965 GB, free: 12.32 MB / 462.1 MB
Notification: Performance of NFFlatten.collectFunctions: time 0.02361/0.5324, allocations: 7.243 MB / 0.6035 GB, free: 5.07 MB / 462.1 MB
Notification: Performance of NFScalarize.scalarize: time 0.0006895/0.5331, allocations: 287.1 kB / 0.6038 GB, free: 4.789 MB / 462.1 MB
Notification: Performance of NFVerifyModel.verify: time 0.001062/0.5342, allocations: 446 kB / 0.6042 GB, free: 4.352 MB / 462.1 MB
Notification: Performance of NFConvertDAE.convert: time 0.01118/0.5454, allocations: 4.958 MB / 0.6091 GB, free: 15.38 MB / 478.1 MB
Notification: Performance of FrontEnd - DAE generated: time 5.731e-06/0.5454, allocations: 3.984 kB / 0.6091 GB, free: 15.38 MB / 478.1 MB
Notification: Performance of FrontEnd: time 1.744e-06/0.5454, allocations: 0 / 0.6091 GB, free: 15.38 MB / 478.1 MB
Notification: Performance of Transformations before backend: time 1.167e-05/0.5454, allocations: 0 / 0.6091 GB, free: 15.38 MB / 478.1 MB
Notification: Model statistics after passing the front-end and creating the data structures used by the back-end:
 * Number of equations: 160
 * Number of variables: 160
Notification: Performance of Generate backend data structure: time 0.003789/0.5492, allocations: 1.621 MB / 0.6107 GB, free: 13.71 MB / 478.1 MB
Notification: Performance of prepare preOptimizeDAE: time 4.204e-05/0.5493, allocations: 8.031 kB / 0.6107 GB, free: 13.7 MB / 478.1 MB
Notification: Performance of preOpt normalInlineFunction (simulation): time 0.00152/0.5508, allocations: 227.8 kB / 0.6109 GB, free: 13.48 MB / 478.1 MB
Notification: Performance of preOpt evaluateParameters (simulation): time 0.0008954/0.5517, allocations: 0.5676 MB / 0.6115 GB, free: 12.87 MB / 478.1 MB
Notification: Performance of preOpt simplifyIfEquations (simulation): time 0.000128/0.5518, allocations: 113.2 kB / 0.6116 GB, free: 12.74 MB / 478.1 MB
Notification: Performance of preOpt expandDerOperator (simulation): time 0.0001046/0.552, allocations: 60.12 kB / 0.6116 GB, free: 12.68 MB / 478.1 MB
Notification: Performance of preOpt clockPartitioning (simulation): time 0.002023/0.554, allocations: 1.079 MB / 0.6127 GB, free: 11.5 MB / 478.1 MB
Notification: Performance of preOpt findStateOrder (simulation): time 2.49e-05/0.554, allocations: 3.938 kB / 0.6127 GB, free: 11.49 MB / 478.1 MB
Notification: Performance of preOpt replaceEdgeChange (simulation): time 8.172e-05/0.5541, allocations: 32 kB / 0.6127 GB, free: 11.46 MB / 478.1 MB
Notification: Performance of preOpt inlineArrayEqn (simulation): time 5.823e-05/0.5542, allocations: 44.97 kB / 0.6128 GB, free: 11.42 MB / 478.1 MB
Notification: Performance of preOpt removeEqualRHS (simulation): time 0.001588/0.5558, allocations: 0.8154 MB / 0.6135 GB, free: 10.6 MB / 478.1 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 0.00592/0.5617, allocations: 5.557 MB / 0.619 GB, free: 4.68 MB / 478.1 MB
Notification: Performance of preOpt comSubExp (simulation): time 0.001289/0.563, allocations: 0.5233 MB / 0.6195 GB, free: 4.129 MB / 478.1 MB
Notification: Performance of preOpt resolveLoops (simulation): time 0.000339/0.5634, allocations: 219 kB / 0.6197 GB, free: 3.906 MB / 478.1 MB
Notification: Performance of preOpt evalFunc (simulation): time 0.1091/0.6725, allocations: 47.66 MB / 0.6662 GB, free: 14.63 MB / 0.5294 GB
Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 5.367e-05/0.6726, allocations: 42.55 kB / 0.6663 GB, free: 14.58 MB / 0.5294 GB
Notification: Performance of pre-optimization done (n=39): time 5.21e-06/0.6726, allocations: 3.984 kB / 0.6663 GB, free: 14.58 MB / 0.5294 GB
Notification: Performance of matching and sorting (n=44): time 0.008892/0.6815, allocations: 2.133 MB / 0.6684 GB, free: 12.38 MB / 0.5294 GB
Notification: Performance of inlineWhenForInitialization (initialization): time 0.0001349/0.6817, allocations: 195.9 kB / 0.6685 GB, free: 12.15 MB / 0.5294 GB
Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.001229/0.6829, allocations: 0.6406 MB / 0.6692 GB, free: 11.5 MB / 0.5294 GB
Notification: Performance of collectPreVariables (initialization): time 7.316e-05/0.683, allocations: 29.7 kB / 0.6692 GB, free: 11.46 MB / 0.5294 GB
Notification: Performance of collectInitialEqns (initialization): time 0.0003955/0.6834, allocations: 403.2 kB / 0.6696 GB, free: 11.07 MB / 0.5294 GB
Notification: Performance of collectInitialBindings (initialization): time 0.0001957/0.6836, allocations: 165.7 kB / 0.6697 GB, free: 10.9 MB / 0.5294 GB
Notification: Performance of simplifyInitialFunctions (initialization): time 0.0003086/0.6839, allocations: 158.5 kB / 0.6699 GB, free: 10.74 MB / 0.5294 GB
Notification: Performance of setup shared object (initialization): time 0.0002028/0.6842, allocations: 374.8 kB / 0.6703 GB, free: 10.37 MB / 0.5294 GB
Notification: Performance of preBalanceInitialSystem (initialization): time 0.0005637/0.6847, allocations: 233.9 kB / 0.6705 GB, free: 10.14 MB / 0.5294 GB
Notification: Performance of partitionIndependentBlocks (initialization): time 0.0008731/0.6856, allocations: 0.5899 MB / 0.6711 GB, free: 9.375 MB / 0.5294 GB
Notification: Performance of analyzeInitialSystem (initialization): time 0.001603/0.6872, allocations: 0.8678 MB / 0.6719 GB, free: 8.344 MB / 0.5294 GB
Notification: Performance of solveInitialSystemEqSystem (initialization): time 1.261e-05/0.6873, allocations: 4 kB / 0.6719 GB, free: 8.34 MB / 0.5294 GB
Notification: Performance of matching and sorting (n=96) (initialization): time 0.002147/0.6894, allocations: 0.8917 MB / 0.6728 GB, free: 7.438 MB / 0.5294 GB
Notification: Performance of prepare postOptimizeDAE: time 3.277e-05/0.6895, allocations: 12 kB / 0.6728 GB, free: 7.426 MB / 0.5294 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 2.371e-05/0.6895, allocations: 12 kB / 0.6728 GB, free: 7.414 MB / 0.5294 GB
Notification: Performance of postOpt tearingSystem (initialization): time 0.004396/0.6939, allocations: 277.2 kB / 0.6731 GB, free: 7.141 MB / 0.5294 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.001775/0.6957, allocations: 279.6 kB / 0.6733 GB, free: 6.867 MB / 0.5294 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.002413/0.6981, allocations: 2.117 MB / 0.6754 GB, free: 4.582 MB / 0.5294 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0008962/0.699, allocations: 28 kB / 0.6754 GB, free: 4.555 MB / 0.5294 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 0.000102/0.6991, allocations: 47.98 kB / 0.6755 GB, free: 4.508 MB / 0.5294 GB
Notification: Model statistics after passing the back-end for initialization:
 * Number of independent subsystems: 53
 * Number of states: 0 ()
 * Number of discrete variables: 10 (volume.regularFlow[1],volume.regularFlow[2],volume.inFlow[2],volume.inFlow[1],volume.medium.phase,shortPipe.flowModel.states[2].phase,shortPipe.flowModel.states[1].phase,ambient.state.phase,ambient.medium.phase,fixedMassFlowRate.medium.phase)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for initialization (94):
 * Single equations (assignments): 92
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 0
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 1
 * Torn equation systems: 1
 * Mixed (continuous/discrete) equation systems: 0
Notification: Equation system details (not torn):
 * Constant Jacobian (size): 0 systems
 * Linear Jacobian (size,density): 0 systems
 * Non-linear Jacobian (size): 1 system
   {1}
 * Without analytic Jacobian (size): 0 systems
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
   {(2,1)}
Notification: Performance of prepare postOptimizeDAE: time 0.0005597/0.6997, allocations: 269.4 kB / 0.6757 GB, free: 4.234 MB / 0.5294 GB
Notification: Performance of postOpt lateInlineFunction (simulation): time 0.0002138/0.6999, allocations: 71.16 kB / 0.6758 GB, free: 4.164 MB / 0.5294 GB
Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.003382/0.7033, allocations: 2.006 MB / 0.6778 GB, free: 2.133 MB / 0.5294 GB
Notification: Performance of postOpt inlineArrayEqn (simulation): time 4.02e-05/0.7034, allocations: 27.91 kB / 0.6778 GB, free: 2.105 MB / 0.5294 GB
Notification: Performance of postOpt constantLinearSystem (simulation): time 4.358e-06/0.7034, allocations: 0 / 0.6778 GB, free: 2.105 MB / 0.5294 GB
Notification: Performance of postOpt simplifysemiLinear (simulation): time 1.372e-05/0.7034, allocations: 4.078 kB / 0.6778 GB, free: 2.102 MB / 0.5294 GB
Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.005198/0.7086, allocations: 3.002 MB / 0.6807 GB, free: 15.02 MB / 0.545 GB
Notification: Performance of postOpt simplifyComplexFunction (simulation): time 6.663e-06/0.7087, allocations: 4.062 kB / 0.6807 GB, free: 15.02 MB / 0.545 GB
Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.00102/0.7097, allocations: 183.8 kB / 0.6809 GB, free: 14.84 MB / 0.545 GB
Notification: Performance of postOpt tearingSystem (simulation): time 0.001711/0.7114, allocations: 299.9 kB / 0.6812 GB, free: 14.55 MB / 0.545 GB
Notification: Performance of postOpt inputDerivativesUsed (simulation): time 3.995e-05/0.7115, allocations: 12 kB / 0.6812 GB, free: 14.54 MB / 0.545 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.00172/0.7132, allocations: 2.187 MB / 0.6833 GB, free: 12.18 MB / 0.545 GB
Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 2.034e-06/0.7132, allocations: 0 / 0.6833 GB, free: 12.18 MB / 0.545 GB
Notification: Performance of postOpt symbolicJacobian (simulation): time 0.002387/0.7156, allocations: 1.933 MB / 0.6852 GB, free: 10.22 MB / 0.545 GB
Notification: Performance of postOpt removeConstants (simulation): time 0.0003697/0.716, allocations: 227.6 kB / 0.6854 GB, free: 9.98 MB / 0.545 GB
Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 0.0001177/0.7161, allocations: 31.69 kB / 0.6855 GB, free: 9.949 MB / 0.545 GB
Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.0004209/0.7165, allocations: 24.11 kB / 0.6855 GB, free: 9.926 MB / 0.545 GB
Notification: Performance of postOpt findZeroCrossings (simulation): time 8.946e-05/0.7166, allocations: 32.34 kB / 0.6855 GB, free: 9.895 MB / 0.545 GB
Notification: Performance of postOpt collapseArrayExpressions (simulation): time 3.828e-05/0.7167, allocations: 19.98 kB / 0.6855 GB, free: 9.875 MB / 0.545 GB
Notification: Performance of sorting global known variables: time 0.0007707/0.7175, allocations: 0.5693 MB / 0.6861 GB, free: 9.312 MB / 0.545 GB
Notification: Performance of sort global known variables: time 1.533e-06/0.7175, allocations: 0 / 0.6861 GB, free: 9.312 MB / 0.545 GB
Notification: Performance of remove unused functions: time 0.003785/0.7213, allocations: 1.089 MB / 0.6872 GB, free: 8.223 MB / 0.545 GB
Notification: Model statistics after passing the back-end for simulation:
 * Number of independent subsystems: 3
 * Number of states: 2 (volume.medium.p,volume.medium.T)
 * Number of discrete variables: 12 ($cse3.phase,$cse3.region,$cse4.phase,$cse4.region,$cse5.phase,$cse5.region,$cse6.phase,$cse6.region,$cse8.phase,$cse8.region,$cse9.phase,$cse9.region)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for simulation (48):
 * Single equations (assignments): 40
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 6
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 1
 * Torn equation systems: 1
 * Mixed (continuous/discrete) equation systems: 0
Notification: Equation system details (not torn):
 * Constant Jacobian (size): 0 systems
 * Linear Jacobian (size,density): 0 systems
 * Non-linear Jacobian (size): 1 system
   {1}
 * Without analytic Jacobian (size): 0 systems
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
   {(2,1)}
Notification: Performance of Backend phase and start with SimCode phase: time 0.00445/0.7257, allocations: 1.199 MB / 0.6883 GB, free: 7.027 MB / 0.545 GB
Notification: Performance of simCode: created initialization part: time 0.00218/0.7279, allocations: 0.9285 MB / 0.6892 GB, free: 6.102 MB / 0.545 GB
Notification: Performance of simCode: created event and clocks part: time 4.859e-06/0.7279, allocations: 0 / 0.6892 GB, free: 6.102 MB / 0.545 GB
Notification: Performance of simCode: created simulation system equations: time 0.001258/0.7292, allocations: 0.6358 MB / 0.6899 GB, free: 5.469 MB / 0.545 GB
Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.002158/0.7314, allocations: 409.2 kB / 0.6902 GB, free: 5.078 MB / 0.545 GB
Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.003201/0.7346, allocations: 2.122 MB / 0.6923 GB, free: 2.926 MB / 0.545 GB
Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0006643/0.7353, allocations: 1.089 MB / 0.6934 GB, free: 1.809 MB / 0.545 GB
Notification: Performance of simCode: alias equations: time 0.0007387/0.736, allocations: 357.9 kB / 0.6937 GB, free: 1.457 MB / 0.545 GB
Notification: Performance of simCode: all other stuff during SimCode phase: time 0.0001381/0.7362, allocations: 63.44 kB / 0.6938 GB, free: 1.395 MB / 0.545 GB
Notification: Performance of SimCode: time 5.41e-07/0.7362, allocations: 0 / 0.6938 GB, free: 1.395 MB / 0.545 GB
Notification: Performance of Templates: time 0.3028/1.039, allocations: 45.47 MB / 0.7382 GB, free: 194.3 MB / 0.5762 GB
make -j1 -f ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.makefile
(rm -f ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.pipe ; mkfifo ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.pipe ; head -c 1048576 < ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.pipe >> ../files/ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.sim & ./ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT  -abortSlowSimulation -alarm=480  -emit_protected -lv LOG_STATS > ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.pipe 2>&1)
diffSimulationResults("ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT_res.mat","/var/lib/jenkins/ws/OpenModelicaLibraryTestingWork/Reference-modelica.org/ReferenceResults/MAP-LIB_ReferenceResults/v4.0.0/ModelicaTest/Media/TestsWithFluid/MediaTestModels/Water/WaterIF97_pT/WaterIF97_pT.csv","/var/lib/jenkins/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/files/ModelicaTest_4.0.0_ModelicaTest.Media.TestsWithFluid.MediaTestModels.Water.WaterIF97_pT.diff",relTol=0.003,relTolDiffMinMax=0.003,rangeDelta=0.001)
Reference file matches