Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries --ompython_omhome=/usr Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.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/Buildings 10.1.1-maint.10.0.x/package.mo", uses=false)
Using package Buildings with version 10.1.1 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 10.1.1-maint.10.0.x/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(Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|grid.P.real|grid.P.apparent",fileNamePrefix="Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid")
translateModel(Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|grid.P.real|grid.P.apparent",fileNamePrefix="Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid")
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.001286/0.001286, allocations: 107.7 kB / 16.41 MB, free: 5.977 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.001319/0.001319, allocations: 188.3 kB / 17.34 MB, free: 5.586 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.396/1.396, allocations: 222.9 MB / 241 MB, free: 15.09 MB / 206.1 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 10.1.1-maint.10.0.x/package.mo): time 2.461/2.461, allocations: 437 MB / 0.7112 GB, free: 4.379 MB / 0.5762 GB
Notification: Performance of FrontEnd - loaded program: time 0.002279/0.002279, allocations: 64.11 kB / 1.019 GB, free: 9.434 MB / 0.795 GB
Notification: Performance of FrontEnd - Absyn->SCode: time 0.986/0.9883, allocations: 151.6 MB / 1.167 GB, free: 3.871 MB / 0.8887 GB
Notification: Performance of NFInst.instantiate(Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid): time 0.004939/0.9932, allocations: 2.896 MB / 1.17 GB, free: 0.9609 MB / 0.8887 GB
Notification: Performance of NFInst.instExpressions: time 0.003167/0.9964, allocations: 1.8 MB / 1.172 GB, free: 15.15 MB / 0.9044 GB
Notification: Performance of NFInst.updateImplicitVariability: time 0.0002234/0.9967, allocations: 7.938 kB / 1.172 GB, free: 15.14 MB / 0.9044 GB
Notification: Performance of NFTyping.typeComponents: time 0.0008505/0.9976, allocations: 235 kB / 1.172 GB, free: 14.91 MB / 0.9044 GB
Notification: Performance of NFTyping.typeBindings: time 0.0006035/0.9982, allocations: 203.1 kB / 1.172 GB, free: 14.71 MB / 0.9044 GB
Notification: Performance of NFTyping.typeClassSections: time 0.000633/0.9988, allocations: 231.4 kB / 1.173 GB, free: 14.48 MB / 0.9044 GB
Notification: Performance of NFFlatten.flatten: time 0.0004528/0.9993, allocations: 311 kB / 1.173 GB, free: 14.18 MB / 0.9044 GB
Notification: Performance of NFFlatten.resolveConnections: time 0.0003579/0.9997, allocations: 182.3 kB / 1.173 GB, free: 14 MB / 0.9044 GB
Notification: Performance of NFEvalConstants.evaluate: time 0.0002522/0.9999, allocations: 127.5 kB / 1.173 GB, free: 13.87 MB / 0.9044 GB
Notification: Performance of NFSimplifyModel.simplify: time 0.0003342/1, allocations: 147.5 kB / 1.173 GB, free: 13.73 MB / 0.9044 GB
Notification: Performance of NFPackage.collectConstants: time 6.668e-05/1, allocations: 20 kB / 1.173 GB, free: 13.71 MB / 0.9044 GB
Notification: Performance of NFFlatten.collectFunctions: time 0.0005184/1.001, allocations: 283.5 kB / 1.174 GB, free: 13.43 MB / 0.9044 GB
Notification: Performance of NFScalarize.scalarize: time 0.0001131/1.001, allocations: 79.8 kB / 1.174 GB, free: 13.35 MB / 0.9044 GB
Notification: Performance of NFVerifyModel.verify: time 0.0001365/1.001, allocations: 123.4 kB / 1.174 GB, free: 13.23 MB / 0.9044 GB
Notification: Performance of NFConvertDAE.convert: time 0.0006802/1.002, allocations: 436.4 kB / 1.174 GB, free: 12.81 MB / 0.9044 GB
Notification: Performance of FrontEnd - DAE generated: time 5.771e-06/1.002, allocations: 0 / 1.174 GB, free: 12.81 MB / 0.9044 GB
Notification: Performance of FrontEnd: time 1.323e-06/1.002, allocations: 0 / 1.174 GB, free: 12.81 MB / 0.9044 GB
Notification: Performance of Transformations before backend: time 1.331e-05/1.002, allocations: 0 / 1.174 GB, free: 12.81 MB / 0.9044 GB
Notification: Model statistics after passing the front-end and creating the data structures used by the back-end:
 * Number of equations: 53
 * Number of variables: 53
Notification: Performance of Generate backend data structure: time 0.001009/1.003, allocations: 0.5457 MB / 1.175 GB, free: 12.21 MB / 0.9044 GB
Notification: Performance of prepare preOptimizeDAE: time 4.033e-05/1.003, allocations: 15.97 kB / 1.175 GB, free: 12.2 MB / 0.9044 GB
Notification: Performance of preOpt normalInlineFunction (simulation): time 0.0009886/1.004, allocations: 112.5 kB / 1.175 GB, free: 12.09 MB / 0.9044 GB
Notification: Performance of preOpt evaluateParameters (simulation): time 0.0003908/1.004, allocations: 259.9 kB / 1.175 GB, free: 11.79 MB / 0.9044 GB
Notification: Performance of preOpt simplifyIfEquations (simulation): time 2.795e-05/1.004, allocations: 16.73 kB / 1.175 GB, free: 11.78 MB / 0.9044 GB
Notification: Performance of preOpt expandDerOperator (simulation): time 4.657e-05/1.004, allocations: 20.36 kB / 1.175 GB, free: 11.76 MB / 0.9044 GB
Notification: Performance of preOpt clockPartitioning (simulation): time 0.0006444/1.005, allocations: 386.5 kB / 1.175 GB, free: 11.35 MB / 0.9044 GB
Notification: Performance of preOpt findStateOrder (simulation): time 1.413e-05/1.005, allocations: 0 / 1.175 GB, free: 11.35 MB / 0.9044 GB
Notification: Performance of preOpt replaceEdgeChange (simulation): time 3.198e-05/1.005, allocations: 11.98 kB / 1.175 GB, free: 11.34 MB / 0.9044 GB
Notification: Performance of preOpt inlineArrayEqn (simulation): time 5.553e-05/1.005, allocations: 24.31 kB / 1.175 GB, free: 11.31 MB / 0.9044 GB
Notification: Performance of preOpt removeEqualRHS (simulation): time 0.0006918/1.006, allocations: 336.6 kB / 1.176 GB, free: 10.98 MB / 0.9044 GB
Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.002107/1.008, allocations: 1.748 MB / 1.178 GB, free: 9.102 MB / 0.9044 GB
Notification: Performance of preOpt comSubExp (simulation): time 0.0007214/1.009, allocations: 333 kB / 1.178 GB, free: 8.758 MB / 0.9044 GB
Notification: Performance of preOpt resolveLoops (simulation): time 0.0002619/1.009, allocations: 149.6 kB / 1.178 GB, free: 8.605 MB / 0.9044 GB
Notification: Performance of preOpt evalFunc (simulation): time 0.0001611/1.009, allocations: 101.1 kB / 1.178 GB, free: 8.488 MB / 0.9044 GB
Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 2.45e-05/1.009, allocations: 30.56 kB / 1.178 GB, free: 8.449 MB / 0.9044 GB
Notification: Performance of pre-optimization done (n=20): time 1.623e-06/1.009, allocations: 0 / 1.178 GB, free: 8.449 MB / 0.9044 GB
Notification: Performance of matching and sorting (n=21): time 0.00138/1.011, allocations: 0.602 MB / 1.179 GB, free: 7.82 MB / 0.9044 GB
Notification: Performance of inlineWhenForInitialization (initialization): time 4.353e-05/1.011, allocations: 77.11 kB / 1.179 GB, free: 7.727 MB / 0.9044 GB
Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.0002664/1.011, allocations: 211.8 kB / 1.179 GB, free: 7.512 MB / 0.9044 GB
Notification: Performance of collectPreVariables (initialization): time 2.545e-05/1.011, allocations: 29.7 kB / 1.179 GB, free: 7.477 MB / 0.9044 GB
Notification: Performance of collectInitialEqns (initialization): time 0.0001037/1.011, allocations: 163.8 kB / 1.179 GB, free: 7.312 MB / 0.9044 GB
Notification: Performance of collectInitialBindings (initialization): time 6.049e-05/1.011, allocations: 71 kB / 1.179 GB, free: 7.242 MB / 0.9044 GB
Notification: Performance of simplifyInitialFunctions (initialization): time 0.0001093/1.011, allocations: 65.88 kB / 1.179 GB, free: 7.172 MB / 0.9044 GB
Notification: Performance of setup shared object (initialization): time 0.0001348/1.011, allocations: 330.8 kB / 1.18 GB, free: 6.84 MB / 0.9044 GB
Notification: Performance of preBalanceInitialSystem (initialization): time 0.0002982/1.012, allocations: 137.9 kB / 1.18 GB, free: 6.703 MB / 0.9044 GB
Notification: Performance of partitionIndependentBlocks (initialization): time 0.000352/1.012, allocations: 220.5 kB / 1.18 GB, free: 6.453 MB / 0.9044 GB
Notification: Performance of analyzeInitialSystem (initialization): time 0.0006327/1.013, allocations: 376.7 kB / 1.18 GB, free: 6.051 MB / 0.9044 GB
Notification: Performance of solveInitialSystemEqSystem (initialization): time 2.244e-06/1.013, allocations: 3.938 kB / 1.18 GB, free: 6.047 MB / 0.9044 GB
Notification: Performance of matching and sorting (n=33) (initialization): time 0.0009297/1.014, allocations: 438.7 kB / 1.181 GB, free: 5.609 MB / 0.9044 GB
Notification: Performance of prepare postOptimizeDAE: time 1.648e-05/1.014, allocations: 4 kB / 1.181 GB, free: 5.605 MB / 0.9044 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 9.077e-06/1.014, allocations: 4 kB / 1.181 GB, free: 5.602 MB / 0.9044 GB
Notification: Performance of postOpt tearingSystem (initialization): time 0.00024/1.014, allocations: 44.77 kB / 1.181 GB, free: 5.555 MB / 0.9044 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0003593/1.014, allocations: 71.88 kB / 1.181 GB, free: 5.484 MB / 0.9044 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.001505/1.016, allocations: 1.615 MB / 1.182 GB, free: 3.723 MB / 0.9044 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0003321/1.016, allocations: 39.95 kB / 1.182 GB, free: 3.684 MB / 0.9044 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 3.08e-05/1.016, allocations: 16 kB / 1.182 GB, free: 3.668 MB / 0.9044 GB
Notification: Performance of preBalanceInitialSystem (initialization_lambda0): time 0.0003902/1.017, allocations: 242.2 kB / 1.183 GB, free: 3.43 MB / 0.9044 GB
Notification: Performance of partitionIndependentBlocks (initialization_lambda0): time 0.0003358/1.017, allocations: 215.5 kB / 1.183 GB, free: 3.18 MB / 0.9044 GB
Notification: Performance of analyzeInitialSystem (initialization_lambda0): time 0.0005748/1.018, allocations: 357.1 kB / 1.183 GB, free: 2.793 MB / 0.9044 GB
Notification: Performance of solveInitialSystemEqSystem (initialization_lambda0): time 5.691e-06/1.018, allocations: 4 kB / 1.183 GB, free: 2.789 MB / 0.9044 GB
Notification: Performance of matching and sorting (n=33) (initialization_lambda0): time 0.0008592/1.018, allocations: 419.9 kB / 1.184 GB, free: 2.371 MB / 0.9044 GB
Notification: Performance of prepare postOptimizeDAE: time 1.208e-05/1.018, allocations: 8 kB / 1.184 GB, free: 2.363 MB / 0.9044 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 5.039e-06/1.018, allocations: 4 kB / 1.184 GB, free: 2.359 MB / 0.9044 GB
Notification: Performance of postOpt tearingSystem (initialization): time 0.000145/1.019, allocations: 36.83 kB / 1.184 GB, free: 2.32 MB / 0.9044 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0003182/1.019, allocations: 80.12 kB / 1.184 GB, free: 2.242 MB / 0.9044 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.001377/1.02, allocations: 1.604 MB / 1.185 GB, free: 496 kB / 0.9044 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0003042/1.021, allocations: 35.81 kB / 1.185 GB, free: 460 kB / 0.9044 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 2.463e-05/1.021, allocations: 12.12 kB / 1.185 GB, free: 448 kB / 0.9044 GB
Notification: Model statistics after passing the back-end for initialization:
 * Number of independent subsystems: 12
 * Number of states: 0 ()
 * Number of discrete variables: 0 ()
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for initialization (31):
 * Single equations (assignments): 30
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 0
 * 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): 1 system
   {(1,2,100.0%)}
 * Non-linear torn systems (#iteration vars, #inner vars): 0 systems
Notification: Performance of prepare postOptimizeDAE: time 0.000157/1.021, allocations: 192.2 kB / 1.186 GB, free: 248 kB / 0.9044 GB
Notification: Performance of postOpt lateInlineFunction (simulation): time 7.788e-05/1.021, allocations: 31.73 kB / 1.186 GB, free: 216 kB / 0.9044 GB
Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.0007091/1.022, allocations: 352.1 kB / 1.186 GB, free: 15.86 MB / 0.92 GB
Notification: Performance of postOpt inlineArrayEqn (simulation): time 5.05e-06/1.022, allocations: 4 kB / 1.186 GB, free: 15.86 MB / 0.92 GB
Notification: Performance of postOpt constantLinearSystem (simulation): time 3.496e-06/1.022, allocations: 3.938 kB / 1.186 GB, free: 15.85 MB / 0.92 GB
Notification: Performance of postOpt simplifysemiLinear (simulation): time 5.31e-06/1.022, allocations: 0 / 1.186 GB, free: 15.85 MB / 0.92 GB
Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.001513/1.023, allocations: 0.9638 MB / 1.187 GB, free: 14.81 MB / 0.92 GB
Notification: Performance of postOpt simplifyComplexFunction (simulation): time 5.671e-06/1.023, allocations: 7.938 kB / 1.187 GB, free: 14.8 MB / 0.92 GB
Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.0002458/1.023, allocations: 48.11 kB / 1.187 GB, free: 14.75 MB / 0.92 GB
Notification: Performance of postOpt tearingSystem (simulation): time 0.0001267/1.024, allocations: 40.83 kB / 1.187 GB, free: 14.71 MB / 0.92 GB
Notification: Performance of postOpt inputDerivativesUsed (simulation): time 2.268e-05/1.024, allocations: 11.98 kB / 1.187 GB, free: 14.7 MB / 0.92 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.001181/1.025, allocations: 1.512 MB / 1.188 GB, free: 13.04 MB / 0.92 GB
Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 5.3e-06/1.025, allocations: 7.938 kB / 1.188 GB, free: 13.04 MB / 0.92 GB
Notification: Performance of postOpt symbolicJacobian (simulation): time 0.0007036/1.026, allocations: 0.5294 MB / 1.189 GB, free: 12.47 MB / 0.92 GB
Notification: Performance of postOpt removeConstants (simulation): time 0.0001563/1.026, allocations: 128.7 kB / 1.189 GB, free: 12.32 MB / 0.92 GB
Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 3.434e-05/1.026, allocations: 11.88 kB / 1.189 GB, free: 12.31 MB / 0.92 GB
Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.0002715/1.026, allocations: 27.97 kB / 1.189 GB, free: 12.29 MB / 0.92 GB
Notification: Performance of postOpt findZeroCrossings (simulation): time 6.896e-05/1.026, allocations: 23.97 kB / 1.189 GB, free: 12.26 MB / 0.92 GB
Notification: Performance of postOpt collapseArrayExpressions (simulation): time 1.597e-05/1.026, allocations: 4 kB / 1.189 GB, free: 12.26 MB / 0.92 GB
Notification: Performance of sorting global known variables: time 0.000198/1.026, allocations: 166.8 kB / 1.189 GB, free: 12.09 MB / 0.92 GB
Notification: Performance of sort global known variables: time 1.41e-07/1.026, allocations: 0 / 1.189 GB, free: 12.09 MB / 0.92 GB
Notification: Performance of remove unused functions: time 0.0006348/1.027, allocations: 108 kB / 1.189 GB, free: 11.99 MB / 0.92 GB
Notification: Model statistics after passing the back-end for simulation:
 * Number of independent subsystems: 8
 * Number of states: 0 ()
 * Number of discrete variables: 0 ()
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for simulation (21):
 * Single equations (assignments): 20
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 0
 * 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): 1 system
   {(1,2,100.0%)}
 * Non-linear torn systems (#iteration vars, #inner vars): 0 systems
Notification: Performance of Backend phase and start with SimCode phase: time 0.0001583/1.027, allocations: 121.5 kB / 1.19 GB, free: 11.86 MB / 0.92 GB
Notification: Performance of simCode: created initialization part: time 0.001474/1.029, allocations: 0.7598 MB / 1.19 GB, free: 11.08 MB / 0.92 GB
Notification: Performance of simCode: created event and clocks part: time 3.536e-06/1.029, allocations: 0 / 1.19 GB, free: 11.08 MB / 0.92 GB
Notification: Performance of simCode: created simulation system equations: time 0.0004042/1.029, allocations: 271.9 kB / 1.191 GB, free: 10.8 MB / 0.92 GB
Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.0004893/1.03, allocations: 35.62 kB / 1.191 GB, free: 10.77 MB / 0.92 GB
Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.001035/1.031, allocations: 0.5924 MB / 1.191 GB, free: 10.12 MB / 0.92 GB
Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0003837/1.031, allocations: 0.7678 MB / 1.192 GB, free: 9.328 MB / 0.92 GB
Notification: Performance of simCode: all other stuff during SimCode phase: time 9.795e-05/1.031, allocations: 27.42 kB / 1.192 GB, free: 9.301 MB / 0.92 GB
Notification: Performance of SimCode: time 2.2e-07/1.031, allocations: 0 / 1.192 GB, free: 9.301 MB / 0.92 GB
Notification: Performance of Templates: time 0.006894/1.038, allocations: 4.328 MB / 1.196 GB, free: 4.977 MB / 0.92 GB
make -j1 -f Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.makefile
(rm -f Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.pipe ; mkfifo Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.pipe ; head -c 1048576 < Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.pipe >> ../files/Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.sim & ./Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid  -abortSlowSimulation -alarm=480  -emit_protected -lv LOG_STATS > Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.pipe 2>&1)
diffSimulationResults("Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid_res.mat","/mnt/ReferenceFiles/Buildings/csv/maint_10.0.x/Buildings_Electrical_AC_OnePhase_Examples_GeneratorLoadGrid.csv","/var/lib/jenkins1/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/files/Buildings_10_Buildings.Electrical.AC.OnePhase.Examples.GeneratorLoadGrid.diff",relTol=0.003,relTolDiffMinMax=0.003,rangeDelta=0.001)
Reference file matches