Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.

  • New elliptic model (grudge/models/elliptic.py)

    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:
      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.

  • Model export

    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.

  • Convergence tests (test/test_elliptic.py)

    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:
      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f

CopilotAI linked an issue Apr 17, 2026 that may be closed by this pull request
Implement interior penalty DG #406
Open
CopilotAI changed the title [WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI requested a review from inducerApril 17, 2026 15:21
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
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Apr 17, 2026•

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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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inducer with Copilot wants to merge 2 commits into
mainfrom 
copilot/implement-interior-penalty-dg
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
inducer with Copilot wants to merge 2 commits into
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CopilotAI
commented
Apr 17, 2026•

edited

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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
inducer with Copilot wants to merge 2 commits into
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CopilotAI
commented
Apr 17, 2026•

edited

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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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Implement interior penalty DG


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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
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CopilotAI
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Apr 17, 2026•

edited

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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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Implement interior penalty DG


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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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mainfrom 
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Draft
Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
inducer with Copilot wants to merge 2 commits into
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CopilotAI
commented
Apr 17, 2026•

edited

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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
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Apr 17, 2026
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closed
by this pull request


Implement interior penalty DG
#406

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CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage - #407
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Add SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverage#407
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copilot/implement-interior-penalty-dg
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This PR adds an interior-penalty DG elliptic model implementing the SIPG bilinear form shown in the issue (volume diffusion term plus symmetric consistency and penalty face terms). It also adds manufactured-solution convergence coverage on a square for both inhomogeneous Dirichlet and Neumann boundary data.
  • New elliptic model (grudge/models/elliptic.py)
    • Adds InteriorPenaltyEllipticOperator.
    • Supports configurable diffusion coefficient kappa and penalty scaling via penalty_factor.
    • Implements interior-face flux assembly with jump/average structure and ( \alpha_e / h_e ) penalty scaling.
    • Supports inhomogeneous boundary data:

      • dirichlet_tag, dirichlet_bc
      • neumann_tag, neumann_bc
    • Accepts scalar, field, or callable BC inputs.
  • Model export
    • Re-exports InteriorPenaltyEllipticOperator from grudge/models/__init__.py for direct import from grudge.models.
  • Convergence tests (test/test_elliptic.py)
    • Adds h-convergence test with a quadratic manufactured solution on a square mesh.
    • Covers both boundary-condition modes:

      • all-Dirichlet
      • all-Neumann
    • Uses the operator residual against the known source term to verify expected convergence behavior across mesh refinement.
fromgrudge.models.ellipticimportInteriorPenaltyEllipticOperatorfrommeshmode.meshimportBTAG_ALL, BTAG_NONEelliptic=InteriorPenaltyEllipticOperator(
dcoll,
kappa=1.0,
penalty_factor=10.0,
dirichlet_tag=BTAG_ALL,
dirichlet_bc=u_boundary, # scalar / DOFArray / callableneumann_tag=BTAG_NONE,
)
residual=elliptic.operator(u) -f
CopilotAI
linked an issue
Apr 17, 2026
that may be
closed
by this pull request


Implement interior penalty DG
#406

Open

CopilotAI
changed the title
[WIP] Add interior penalty DG implementation in elliptic.pyAdd SIPG elliptic operator with inhomogeneous Dirichlet/Neumann BC support and convergence coverageApr 17, 2026
CopilotAI
requested a review
from inducerApril 17, 2026 15:21
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Reviewers

@inducerinducerAwaiting requested review from inducer

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Implement interior penalty DG


2 participants

@inducer