Analyzing a large datasets

[oMuransky]

Hi Ralf,

When trying to calculate grains in large EBSD map I'm getting a following error - I tried a few things but I don't seem to be able to find solution. Any advice would be great - I can share the data if needed it is stitched from 9 individual EBSD maps and stitching was done in Aztec.

Thank you, Ondrej

CODE

[grains,ebsd.grainId,ebsd.mis2mean] = ... calcGrains(ebsd('indexed'),'threshold',[10degree 2degree]);

ERROR

Error using matlab.internal.math.qhull QH7074 qhull warning: more than 16777215 ridges. ID field overflows and two ridges may have the same identifier. Otherwise output ok. QH7074 qhull warning: more than 16777215 ridges. ID field overflows and two ridges may have the same identifier. Otherwise output ok. QH7074 qhull warning: more than 16777215 ridges. ID field overflows and two ridges may have the same identifier. Otherwise output ok. QH7074 qhull warning: more than 16777215 ridges. ID field overflows and two ridges may have the same identifier. Otherwise output ok. QH6159 qhull input error: more than 16777215 vertices. ID field overflows and two vertices may have the same identifier. Vertices not sorted correctly.

While executing: | qhull v Q5 Q6 Qs Options selected for Qhull 2010.1 2010/01/14: run-id 1558329480 voronoi Q5-no-check-outer Q6-no-concave-merge Qsearch-initial-simplex _pre-merge _zero-centrum Pgood _max-width 1.2e+07 Error-roundoff 1e-08 _one-merge 7.2e-08 Visible-distance 2.1e-08 U-coplanar-distance 2.1e-08 Width-outside 4.1e-08 _wide-facet 1.2e-07 Last point added to hull was p8276830. Last merge was #25420530.

At error exit:

Voronoi diagram by the convex hull of 18638723 points in 3-d:

Number of Voronoi regions: 16777214 Total number of nearly incident points: 1861509 Number of Voronoi vertices: 0 Number of non-simplicial Voronoi vertices: 14814988

Statistics for: | qhull v Q5 Q6 Qs

Number of points processed: 16777215 Number of hyperplanes created: 58310209 Number of facets in hull: 18472729 Number of distance tests for qhull: 1420765134 Number of distance tests for merging: 90009511 Number of distance tests for checking: 0 Number of merged facets: 25420530 Maximum distance of merged point above facet: 4.5e-08 (0.5x) Maximum distance of merged vertex below facet: -3.1e-08 (0.4x)

Error in voronoin (line 107) [v, c] = matlab.internal.math.qhull(x', 'v ', opt);

Error in spatialDecomposition (line 35) [V,D] = voronoin([X;dummyCoordinates],{'Q5','Q6','Qs'}); %,'QbB'

Error in EBSD/calcGrains (line 62) [V,F,I_FD] = spatialDecomposition([ebsd.prop.x(:), ebsd.prop.y(:)],ebsd.unitCell,varargin{:});

[ralfHielscher]

You may try the option noQHull to calcGrains.

Ralf.

[oMuransky]

Thank you Ralf. I'll try.

[oMuransky]

Thank you Ralf doing "noQHull" option helped.

[Helanism]

why I try 'noQHull' can not solve it

[Helanism]

My data about 30 millions pixels

[Helanism]

when I use 'noQHull' options it will calculate for hours, it is abnormal