3.3.3.60. NXmicrostructure_odf¶
Status:
base class (contribution), extends NXprocess
Description:
Base class to store an orientation distribution function (ODF). …
Base class to store an orientation distribution function (ODF).
An orientation distribution function is a probability distribution that details how much volume of material has a specific orientation. An ODF is computed from pole figure data in a computational process called pole figure inversion.
Symbols:
n_varphi_two: Number of pixel per varphi section plot along the \(\varphi_2\) slow direction.
n_capital_phi: Number of pixel per varphi section plot along the \(\Phi\) fast direction.
n_varphi_one: Number of pixel per varphi section plot along the \(\varphi_1\) fastest direction.
k: Number of local maxima evaluated in the component analysis.
n_pos: Number of sampled positions in orientation space.
- Groups cited:
Structure:
configuration: (optional) NXparameters ⤆
Details about the algorithm used for computing the ODF.
crystal_symmetry_point_group: (optional) NX_CHAR
Point group of the crystal structure of the phase for which the here documen …
Point group of the crystal structure of the phase for which the here documented phase-dependent ODF was computed following the notation of the International Table of Crystallography.
specimen_symmetry_point_group: (optional) NX_CHAR
Point group assumed for additionally considered sample symmetries …
Point group assumed for additionally considered sample symmetries following the notation of the International Table of Crystallography.
kernel_halfwidth: (optional) NX_NUMBER {units=NX_ANGLE}
Halfwidth of the kernel.
kernel_name: (optional) NX_CHAR
Name of the kernel.
resolution: (optional) NX_NUMBER {units=NX_ANGLE}
Resolution of the kernel.
characteristics: (optional) NXprocess
Group to store descriptors for a rough classification of an ODF.
texture_index: (optional) NX_FLOAT {units=NX_DIMENSIONLESS}
The texture index \(t = \int_{\mathcal{SO(3)}} f(R)^{2}dR\) with …
The texture index \(t = \int_{\mathcal{SO(3)}} f(R)^{2}dR\) with \(f(R)\), denoting the ODF is evaluated in orientation space \(\mathcal{SO(3)}\).
The higher it is the texture index the sharper it is the ODF.
kth_extrema: (optional) NXprocess
Group to store descriptors and summary statistics for extrema of the ODF.
extrema: (optional) NX_CHAR
Minima or maxima, if extrema is set to minima values for location and volume …
Minima or maxima, if extrema is set to minima values for location and volume_fraction are sorted in increasing order. If extrema is set to maxima values for location and volume_fraction are sorted in decreasing order. Therefore, the global extremum is always the first entry in location and volume_fraction.
Any of these values:
minima|maximakth: (optional) NX_UINT {units=NX_UNITLESS}
Number of local extrema evaluated
theta: (optional) NX_NUMBER {units=NX_ANGLE}
Disorientation threshold within which intensity of the ODF …
Disorientation threshold within which intensity of the ODF is integrated for the component analysis.
location: (optional) NX_NUMBER (Rank: 2, Dimensions: [k, 3]) {units=NX_ANGLE}
Euler angle representation \(\varphi_1\), \(\Phi\), …
Euler angle representation \(\varphi_1\), \(\Phi\), \(\varphi_2\) of the kth-most maxima in decreasing order of the intensity maximum.
volume_fraction: (optional) NX_NUMBER (Rank: 1, Dimensions: [k]) {units=NX_ANY}
Integrated ODF intensity within a theta angular region of the orientation sp …
Integrated ODF intensity within a theta angular region of the orientation space \(SO3\) about each location (obeying symmetries) as specified for each location.
sampling: (optional) NXprocess
The ODF intensity values (weights) as sampled with a software.
resolution: (optional) NX_NUMBER {units=NX_ANGLE}
Sampling resolution
euler: (optional) NX_NUMBER (Rank: 2, Dimensions: [n_pos, 3]) {units=NX_ANGLE}
Bunge-Euler (i.e. ZXZ convention) locations of each position …
Bunge-Euler (i.e. ZXZ convention) locations of each position in orientation space for which a weight was sampled.
weight: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_pos]) {units=NX_DIMENSIONLESS}
Weight at each sampled position following the order in euler.
phi_two_plot: (optional) NXdata ⤆
Visualization of the ODF intensity as discretized orthogonal sections through …
Visualization of the ODF intensity as discretized orthogonal sections through orientation space parameterized using Bunge-Euler angles.
This is one example of typical default plots used in the texture community in materials engineering.
Mind that the orientation space is a distorted space when it using an Euler angle parameterization. Therefore, equivalent orientations show intensity contributions in eventually multiple locations.
intensity: (optional) NX_NUMBER (Rank: 3, Dimensions: [n_varphi_two, n_capital_phi, n_varphi_one]) {units=NX_DIMENSIONLESS}
ODF intensity at probed locations relative to the intensity of the null mode …
ODF intensity at probed locations relative to the intensity of the null model of a random texture.
varphi_one: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_varphi_one]) {units=NX_ANGLE} ⤆
Pixel center angular position along the \(\varphi_1\) direction.
capital_phi: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_capital_phi]) {units=NX_ANGLE}
Pixel center angular position along the \(\Phi\) direction.
varphi_two: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_varphi_two]) {units=NX_ANGLE} ⤆
Pixel center angular position along the \(\varphi_2\) direction.
Hypertext Anchors¶
List of hypertext anchors for all groups, fields, attributes, links, and symbols defined in this class.