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Z Binned Deformation Gradient Strain Analysis

Compute reference-to-current deformation-gradient strain in z bins.

Selected frame-zero atoms define material bins. For each reported frame, this analyzer fits a translation-free affine deformation gradient and derives the Green-Lagrange strain tensor, engineering shear, principal strains, volume change, and fit diagnostics. Input loading and rendering are out of scope.

Usage context

  • Finite deformation: Measure rotation-invariant local strain through a slab.
  • Fit diagnostics: Retain rank, conditioning, and residual error per z bin.

Request: ZBinnedDeformationGradientStrainRequest

Request configuration for z-binned affine strain fitting.

Fields

Field Type Default Help Choices
z_bins int 20 Number of equal-width z bins.
atom_types Optional[Sequence[str]] Al, N Elements to include; empty selects all atoms.
bin_range str reference Reference-material or current-position bins. reference, current
minimum_atoms int 4 Minimum atoms for an affine fit.
max_condition_number float 1000000000000.0 Reject more ill-conditioned reference fits.
selected_frames Optional[Sequence[int]] Zero-based frames to report.
every int 1 Stride over selected frames.
unwrap bool True Cumulatively unwrap periodic coordinates.
periodic str xyz Periodic axes, such as xy or xyz. none, x, y, z, xy, xz, yz, xyz

Examples

`ZBinnedDeformationGradientStrainRequest(z_bins=10, periodic="xy")`
configures ten fixed material bins in an xy-periodic slab.

Task: ZBinnedDeformationGradientStrainTask

Run z-binned deformation-gradient strain analysis.

Return table and normal-strain profile presentation specifications.

Works on

Analyzer task output payloads.

Parameters

Name Type Description
_result ZBinnedDeformationGradientStrainResult Typed analyzer result.
payload dict[str, Any] Serialized result payload.

Returns

Type Description
list[PresentationSpec] Table and strain-versus-z plot specifications.

Examples

`ZBinnedDeformationGradientStrainTask.recommended_presentations(result, payload)`
returns standard downstream views.

Method: run(data: TrajectoryData, request: ZBinnedDeformationGradientStrainRequest, reporter=None)

Execute z-binned deformation-gradient strain analysis.

Works on

TrajectoryData plus ZBinnedDeformationGradientStrainRequest inputs.

Parameters

Name Type Description
data TrajectoryData Canonical trajectory data.
request ZBinnedDeformationGradientStrainRequest Analysis configuration.
reporter Any, optional Progress reporter accepted by the analyzer interface.

Returns

Type Description
ZBinnedDeformationGradientStrainResult Computed table and request provenance.

Examples

`ZBinnedDeformationGradientStrainTask().run(data, request)` returns
fitted strain and diagnostics for every selected bin.

Result: ZBinnedDeformationGradientStrainResult

Result of z-binned deformation-gradient strain analysis.

Fields

Field Type Default Help Choices
table pd.DataFrame
request ZBinnedDeformationGradientStrainRequest

Examples

`ZBinnedDeformationGradientStrainResult(table=<DataFrame>, request=request)`
preserves computed finite-strain values and their configuration.