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RunMat™ is a registered trademark of Dystr, Inc. MATLAB® is a registered trademark of The MathWorks, Inc. RunMat is not affiliated with, endorsed by, or sponsored by The MathWorks, Inc.

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Builtin Reference
    • fea.boundaryCondition
    • fea.compare
    • fea.domain
    • fea.field
    • fea.interface
    • fea.loadCase
    • fea.material
    • fea.materialAssignment
    • fea.model
    • fea.plan
    • fea.plot
    • fea.results
    • fea.run
    • fea.runOptions
    • fea.step
    • fea.study
    • fea.sweep
    • fea.trends
    • fea.validate

fea.boundaryCondition — Create a typed RunMat FEA boundary condition.

fea.boundaryCondition(id, region, kind, Name, Value, ...) creates a typed boundary-condition object for a RunMat FEA model. This API is native to RunMat rather than a MATLAB compatibility builtin.

Syntax

bc = fea.boundaryCondition(id, region, kind, Name, Value, ...)

Inputs

NameTypeRequiredDefaultDescription
idStringScalarYes—Boundary-condition id.
regionStringScalarYes—Target region id.
kindStringScalarYes—Boundary-condition kind.
Name, ValueAnyVariadic—Numeric fields required by the selected kind.

Returns

NameTypeDescription
resultAnyFEA object or operation result.

Errors

IdentifierWhenMessage
RunMat:fea:LoadFailedA .fea document cannot be read, parsed, or resolved.fea: failed to load FEA document
RunMat:fea:InvalidInputA builtin receives an unsupported argument pattern or object type.fea: invalid input
RunMat:fea:OperationFailedA validation, planning, run, result-query, comparison, or trend operation fails.fea: operation failed
RunMat:fea:InternalAn FEA object or operation result cannot be converted to a RunMat value.fea: internal error

How fea.boundaryCondition works

  • The first three inputs select the boundary-condition id, target region id, and boundary kind.
  • Numeric fields must be finite real numeric scalars. Logical values, arrays with more than one element, and unknown fields are rejected with RunMat:fea:InvalidInput.
  • All eight built-in integer classes are accepted for every numeric field listed below. Each exact integer is converted once to the model's binary64 field using IEEE-754 integer-to-f64 conversion, so sufficiently wide integers can round.

Examples

Prescribe integer-valued rotations

bc = fea.boundaryCondition('rotation', 'tip', 'prescribedRotation', 'rx', int16(0), 'ry', int16(1), 'rz', int16(0));

Create a CFD inlet boundary

bc = fea.boundaryCondition('inlet', 'inlet_face', 'cfdInletVelocity', 'velocityMPerS', uint8(12));

Using fea.boundaryCondition with coding agents

Open a RunMat example with live inputs, then ask the agent to explain how fea.boundaryCondition changes the result.

Run a small fea.boundaryCondition example, explain the result, then change one input and compare the output.

FAQ

Are integer fields stored as integers?⌄

No. Boundary-condition model fields are binary64 values. RunMat preserves the integer until the explicit constructor boundary and then performs one documented IEEE-754 conversion.

Related Fea functions

fea.compare · fea.domain · fea.field · fea.interface · fea.loadCase · fea.material · fea.materialAssignment · fea.model · fea.plan · fea.plot · fea.results · fea.run · fea.runOptions · fea.step · fea.study · fea.sweep · fea.trends · fea.validate

Open-source implementation

Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how fea.boundaryCondition is executed, line by line, in Rust.

  • View the source for fea.boundaryCondition in Rust on GitHub
  • Learn how the RunMat runtime works
  • Found a bug? Open an issue with a minimal reproduction.

About RunMat

RunMat is an open-source runtime that executes MATLAB-syntax code blazing on any GPU. It is licensed under the Apache 2.0 license.

  • RunMat automatically optimizes your math for GPU execution on Apple, Nvidia, and AMD hardware. No code changes needed. Simulations that took hours now take minutes.
  • Start running code in seconds. RunMat runs in the browser, on the desktop, or from the CLI. No license server, no IT ticket.

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On this page
  • Syntax
  • Inputs
  • Returns
  • Errors
  • How fea.boundaryCondition works
  • Examples
  • Prescribe integer-valued rotations
  • Create a CFD inlet boundary
  • Using fea.boundaryCondition with coding agents
  • FAQ
  • Related Fea functions
  • Open-source implementation
  • About RunMat