Introduction

• Documentation
  • About ngsxfem
  • The features of ngsxfem
  • Examples and Documentation
  • Installation
  • List of contributing authors
  • Community guidelines
  • Citing
• Feature details of ngsxfem
  • Tools to work on an “active mesh” only
  • Numerical integration on unfitted geometries described by one level set function
  • Geometries described by multiple level sets
  • Higher order representation of implicit level-set geometries
  • Space-Time Finite Elements for the treatment of moving domain problems
  • Patches for Element Aggregation or Ghost Penalties

Installation

• Installation instructions
  • Installation of ngsxfem
  • Installation through pip (pip3)
    • Releases
    • Development version
  • Installation from source
  • Docker container
    • Jupyter through docker

Demos / jupyter tutorials

• Demonstration files
• Jupyter tutorials

Python interface

• xfem package
  • Submodules
    • xfem.cutmg module
      • CutFemSmoother
        • CutFemSmoother.InterfaceCorrection()
        • CutFemSmoother.Smooth()
        • CutFemSmoother.SmoothBack()
      • EdgePatches()
      • ElemPatches()
      • LinearMGIterator
        • LinearMGIterator.Height()
        • LinearMGIterator.Mult()
        • LinearMGIterator.Update()
        • LinearMGIterator.Width()
        • LinearMGIterator.createVec()
        • LinearMGIterator.getSpaceDim()
      • MultiGridCL
        • MultiGridCL.Height()
        • MultiGridCL.Mult()
        • MultiGridCL.Width()
      • P2TwoGridCL
        • P2TwoGridCL.Mult()
      • VertPatches()
    • xfem.lset_smoothblend module
      • LevelSet_SmoothBlending
        • LevelSet_SmoothBlending.Calc_blend_CF()
      • SmoothBlendingType
        • SmoothBlendingType.BLEND_AUTODETECT
        • SmoothBlendingType.BLEND_FIXED_WIDTH
    • xfem.lset_spacetime module
      • LevelSetMeshAdaptation_Spacetime
        • LevelSetMeshAdaptation_Spacetime.BFI()
        • LevelSetMeshAdaptation_Spacetime.CalcDeformation()
        • LevelSetMeshAdaptation_Spacetime.CalcMaxDistance()
        • LevelSetMeshAdaptation_Spacetime.Integrate()
        • LevelSetMeshAdaptation_Spacetime.Integrator()
        • LevelSetMeshAdaptation_Spacetime.LFI()
        • LevelSetMeshAdaptation_Spacetime.ProjectGFs()
        • LevelSetMeshAdaptation_Spacetime.ProjectOnUpdate()
        • LevelSetMeshAdaptation_Spacetime.interpol_ho()
        • LevelSetMeshAdaptation_Spacetime.interpol_p1()
        • LevelSetMeshAdaptation_Spacetime.levelset_domain()
        • LevelSetMeshAdaptation_Spacetime.order_deform
        • LevelSetMeshAdaptation_Spacetime.order_lset
        • LevelSetMeshAdaptation_Spacetime.order_qn
    • xfem.lsetcurv module
      • LevelSetMeshAdaptation
        • LevelSetMeshAdaptation.BFI()
        • LevelSetMeshAdaptation.CalcDeformation()
        • LevelSetMeshAdaptation.CalcMaxDistance()
        • LevelSetMeshAdaptation.Integrate()
        • LevelSetMeshAdaptation.Integrator()
        • LevelSetMeshAdaptation.LFI()
        • LevelSetMeshAdaptation.MarkForRefinement()
        • LevelSetMeshAdaptation.ProjectGFs()
        • LevelSetMeshAdaptation.ProjectOnUpdate()
        • LevelSetMeshAdaptation.levelset_domain()
        • LevelSetMeshAdaptation.order_deform
        • LevelSetMeshAdaptation.order_lset
        • LevelSetMeshAdaptation.order_qn
    • xfem.mlset module
      • DomainTypeArray
        • DomainTypeArray.Boundary()
        • DomainTypeArray.Compress()
        • DomainTypeArray.GetOuterNormals()
        • DomainTypeArray.Indicator()
        • DomainTypeArray.IndicatorSmoothed()
      • TensorIntersection()
      • TensorUnion()
    • xfem.ngs_check module
      • check_if_ngsolve_newer_than()
    • xfem.utils module
    • xfem.xfem module
      • BitArrayCF
      • COMBINED_DOMAIN_TYPE
        • COMBINED_DOMAIN_TYPE.ANY
        • COMBINED_DOMAIN_TYPE.CDOM_IF
        • COMBINED_DOMAIN_TYPE.CDOM_NEG
        • COMBINED_DOMAIN_TYPE.CDOM_POS
        • COMBINED_DOMAIN_TYPE.HASNEG
        • COMBINED_DOMAIN_TYPE.HASPOS
        • COMBINED_DOMAIN_TYPE.NO
        • COMBINED_DOMAIN_TYPE.UNCUT
        • COMBINED_DOMAIN_TYPE.name
        • COMBINED_DOMAIN_TYPE.value
      • CSpaceTimeFESpace
        • CSpaceTimeFESpace.IsTimeNodeActive()
        • CSpaceTimeFESpace.SetOverrideTime()
        • CSpaceTimeFESpace.SetTime()
        • CSpaceTimeFESpace.TimeFE_nodes()
        • CSpaceTimeFESpace.k_t()
        • CSpaceTimeFESpace.spaceFES
      • CXFESpace
        • CXFESpace.BaseDofOfXDof()
        • CXFESpace.GetCutInfo()
        • CXFESpace.GetDomainNrs()
        • CXFESpace.GetDomainOfDof()
      • CompoundBitArray()
      • CompoundProlongation
        • CompoundProlongation.AddProlongation()
        • CompoundProlongation.Prolongate()
        • CompoundProlongation.Restrict()
        • CompoundProlongation.Update()
      • CreateTimeRestrictedGF()
      • CutDifferentialSymbol
        • CutDifferentialSymbol.order()
        • CutDifferentialSymbol.vb
      • CutInfo
        • CutInfo.GetCutRatios()
        • CutInfo.GetElementsOfType()
        • CutInfo.GetElementsWithThresholdContribution()
        • CutInfo.GetFacetsOfType()
        • CutInfo.Mesh()
        • CutInfo.Update()
      • DOMAIN_TYPE
        • DOMAIN_TYPE.IF
        • DOMAIN_TYPE.NEG
        • DOMAIN_TYPE.POS
        • DOMAIN_TYPE.name
        • DOMAIN_TYPE.value
      • ElementAggregation
        • ElementAggregation.Update()
        • ElementAggregation.element_to_patch
        • ElementAggregation.els_in_nontrivial_patch
        • ElementAggregation.els_in_trivial_patch
        • ElementAggregation.facet_to_patch
        • ElementAggregation.patch_interior_facets
      • ExtensionEmbedding()
      • FacetPatchDifferentialSymbol
      • GCC3FE
      • GetDofsOfElements()
      • GetDofsOfFacets()
      • GetElementsWithNeighborFacets()
      • GetElementsWithSharedVertex()
      • GetFacetsWithNeighborTypes()
      • GlobalNgsxfemVariables
        • GlobalNgsxfemVariables.MultiplyAllEps()
        • GlobalNgsxfemVariables.Output()
        • GlobalNgsxfemVariables.SetDefaults()
        • GlobalNgsxfemVariables.SwitchSIMD()
        • GlobalNgsxfemVariables.do_naive_timeint
        • GlobalNgsxfemVariables.eps_P1_perturbation
        • GlobalNgsxfemVariables.eps_facetpatch_ips
        • GlobalNgsxfemVariables.eps_shifted_eval
        • GlobalNgsxfemVariables.eps_spacetime_cutrule_bisection
        • GlobalNgsxfemVariables.eps_spacetime_fes_node
        • GlobalNgsxfemVariables.eps_spacetime_lset_perturbation
        • GlobalNgsxfemVariables.fixed_point_maxiter_shifted_eval
        • GlobalNgsxfemVariables.max_dist_newton
        • GlobalNgsxfemVariables.naive_timeint_order
        • GlobalNgsxfemVariables.naive_timeint_subdivs
        • GlobalNgsxfemVariables.newton_maxiter
        • GlobalNgsxfemVariables.non_conv_warn_msg_lvl
        • GlobalNgsxfemVariables.simd_eval
      • IntegrateX()
      • IntegrationPointExtrema()
      • InterpolateToP1()
      • MultiLevelsetCutInfo
        • MultiLevelsetCutInfo.GetElementsOfType()
        • MultiLevelsetCutInfo.GetElementsWithContribution()
        • MultiLevelsetCutInfo.Mesh()
        • MultiLevelsetCutInfo.Update()
      • P1Prolongation
        • P1Prolongation.Update()
      • P2CutProlongation
        • P2CutProlongation.Update()
      • P2Prolongation
        • P2Prolongation.Update()
      • PatchwiseSolve()
      • ProjectShift()
      • QUAD_DIRECTION_POLICY
        • QUAD_DIRECTION_POLICY.FALLBACK
        • QUAD_DIRECTION_POLICY.FIRST
        • QUAD_DIRECTION_POLICY.OPTIMAL
        • QUAD_DIRECTION_POLICY.name
        • QUAD_DIRECTION_POLICY.value
      • ReferenceTimeVariable()
      • RefineAtLevelSet()
      • Restrict
        • Restrict.GetBaseSpace()
        • Restrict.active_elements
      • RestrictGFInTime()
      • RestrictedBilinearFormComplex
        • RestrictedBilinearFormComplex.element_restriction
        • RestrictedBilinearFormComplex.facet_restriction
      • RestrictedBilinearFormDouble
        • RestrictedBilinearFormDouble.element_restriction
        • RestrictedBilinearFormDouble.facet_restriction
      • SFESpace()
      • ScalarTimeFE
      • SpaceTimeFESpace()
      • SpaceTimeInterpolateToP1()
      • SpaceTimeVTKOutput
        • SpaceTimeVTKOutput.Do()
      • SymbolicCutBFI()
      • SymbolicCutLFI()
      • SymbolicFacetPatchBFI()
      • TIME_DOMAIN_TYPE
        • TIME_DOMAIN_TYPE.BOTTOM
        • TIME_DOMAIN_TYPE.INTERVAL
        • TIME_DOMAIN_TYPE.TOP
        • TIME_DOMAIN_TYPE.name
        • TIME_DOMAIN_TYPE.value
      • TimeVariableCoefficientFunction
        • TimeVariableCoefficientFunction.FixTime()
        • TimeVariableCoefficientFunction.IsFixed()
        • TimeVariableCoefficientFunction.UnfixTime()
      • XFESpace()
      • XToNegPos()
      • dn()
      • fix_tref_coef()
      • fix_tref_gf()
      • fix_tref_proxy()
      • shifted_eval()
  • Module contents
    • (ngs)xfem
    • AggEmbedding()
    • CutRatioGF()
    • DrawDC()
    • DrawDiscontinuous_std()
    • DrawDiscontinuous_webgui()
    • DummyScene
      • DummyScene.Redraw()
    • HAS()
    • IndicatorCF()
    • Integrate()
    • Integrate_X_special_args()
    • IsCut()
    • MakeDiscontinuousDraw()
    • NoDeformation
      • NoDeformation.CalcDeformation()
    • RestrictedBilinearForm()
    • SpaceTimeSet()
    • SpaceTimeWeakSet()
    • SymbolicBFI()
    • SymbolicBFIWrapper()
    • SymbolicLFI()
    • SymbolicLFIWrapper()
    • TimeSlider_Draw()
    • TimeSlider_DrawDC()
    • dCut()
    • dFacetPatch()
    • ddtref()
    • dmesh()
    • dt()
    • dtref()
    • dxtref()
    • extend()
    • extend_grad()
    • fix_t()
    • fix_t_coef()
    • fix_t_gf()
    • fix_t_proxy()
    • fix_tref()
    • kappa()
    • neg()
    • neg_grad()
    • pos()
    • pos_grad()

Literature

• Scientific literature using ngsxfem
  • Fictitious domain problems
  • Scalar and Stokes interface problems, such as two-phase flow problems
  • Fractured Porous Media
  • PDEs on moving domains: Space-time methods
  • PDEs on moving domains: Eulerian time-stepping
  • Fluid structure interaction
  • Surface PDEs
  • Shape optimization
  • Model order reduction and optimal control
  • Space-time discretisations (fitted FEM in space)
  • Reproduction Datasets