quality provides a collection of mesh quality measurements. Together with commands in cmo/addatt a good summary of mesh metrics can be reported or used for further mesh optimization. See Quality Measures.
quality / [quality_type] / [quality_type_options]
The following are definitions for valid
quality-type commands and their
with no arguments writes to screen and outx3dgen or lagrit.out logfile giving volume and aspect ratio distribution information. Aspect ratios and element volumes are binned into 5 bins then totaled, min and max values are also reported.
quality/aspect / [y]
computes the ratio of the radius of the circumsphere to the radius of the inscribed sphere of a tetrahedron. The ratio is multiplied by 3 so that a value of 1 indicates a regular tetrahedron. The display is a count of the number of elements whose aspect ratio falls in each of 7 bins. Option y creates the element attribute named aratio that will contain the value of the aspect ratio for each element. Valid element types are tet and tri, hex, and quad (where the length of the hex or quad diagonals are used).
quality/edge_ratio / [y]
computes the ratio (shortest element edge/longest element edge) and displays a count of the min/max edge ratio in each of 7 bins. Option y creates the element attribute named eratio that will contain the value of the min/max edge ratio of each element.
quality/edge_min / [y]
displays a count of the minimum edge length in each of 7 bins. Option y creates the element attribute named edgemin that will contain the value of the min edge length of each element.
quality/edge_max / [y]
displays a count of the maximum edge length in each of 7 bins. Option y creates the element attribute named edgemax that will contain the value of the max edge length of each element.
quality/angle / gt OR lt / value /
finds the max and min dihedral angles between adjacent faces (or 2D edges) of an element in radians. If the compare option is used, it displays a count of the number of elements with a dihedral angle that is greater than or less than the supplied value. See also cmo/addatt/cmo/ang_ commands for dihedral angle and solid angle calculations.
creates an element based attribute called neg_coup_coeff which is a “negative coupling coefficient” indicator. A value of 1 means the coupling coefficient is OK. Anything less than 1 means it is negative. This is useful when viewing a mesh to find where the negative coupling coefficients occur.
generates some quality measures for quads and displays them after binning them into seven bins. Please see cmo / addatt // quad_quality for details on the quality measures used.
quality/taylor/ fieldname / value /
creates and displays a count of the number of element-edge pairs with a taylor error estimate value whose absolute value is greater than the supplied value. This creates the attribute quality_taylor with length in attribute quality_taylor_len.
quality/volume allows any combination of the
quality_type_options for example:
quality/volume/ number_of_bins / itetclr / lt | gt | eq | ne | xvalue / eltset,get,ename
quality/volume / [number_of_bins] / [ itetclr ]
number_of_bins is an integer value controlling the number of bins in which to distribute the volume values for display. if number_of_bins is 0, then binning of distributed volumes is skipped, and only min and max volumes are reported. number_of_bins must be the 2nd argument to quality if used.
itetclr is a keyword that will give volume information according to the values in the itetclr attribute. Number_of_bins applies to each tetclr value. For each itetclr value, the volume of elements will be totaled.
quality/volume / gt OR lt OR eq OR ne / value
will report volumes based on compare operator and given xvalue, for instance quality/volume/lt 0.0/ will report total number of elements with volumes less than 0.0 It may be used in combination of other volume options. if used with itetclr keyword, values will be reported by itetclr value
quality/volume / eltset, get, eset_name
eltset,get,ename will report volumes on elements in defined eltset can be used in combination with previous options with operations done only on the chosen eltset. itetclr will still report for each of the values in itetclr.
display summary of volume and aspect ratios
display summary of aspect ratio distribution in 7 bins
create attribute aratio and display summary of aspect the aratio distribution
return count of elements with a dihedral angle > 179
run taylor error estimate and return count of element edge pairs with absolute error greater than 1.e-10
quality/volume quality/volume/ 2
The first call will display summary of volumes with 5 bins, the second command will show summary with 2 bins
quality/volume/itetclr quality/volume /itetclr/lt .03 quality/volume/itetclr/eltset,get,e2
All three commands will loop through itetclr (material values) and report a total volume for each itetclr value. The second command will report element volumes lt .03 by the itetclr values. The third command will report element volumes by itetclr values, but only for elements in the set e2
quality quality/ aspect / y quality/ edge_max / y cmo/addatt /cmotri /area_normal/ xyz/ anorm cmo/addatt /cmotri /scalar /xnorm ynorm znorm / anorm cmo/printatt /cmotri / aratio minmax cmo/printatt /cmotri / edgemax minmax cmo/printatt /cmotri / znorm minmax
Example calls using quality and cmo/addatt commands to show mesh quality statistics.
quality epsilonl, epsilonaspect: 1.4360051E-10 2.9612012E-30 -------------------------------------------- elements with aspect ratio < .01: 0 elements with aspect ratio b/w .01 and .02: 0 elements with aspect ratio b/w .02 and .05: 0 elements with aspect ratio b/w .05 and .1 : 0 elements with aspect ratio b/w .1 and .2 : 12020 elements with aspect ratio b/w .2 and .5 : 625891 elements with aspect ratio b/w .5 and 1. : 157053 min aspect ratio = 0.1053E+00 max aspect ratio = 0.7229E+00 epsilonvol: 1.1335396E-05 --------------------------------------- element volumes b/w 0.1667E+02 and 0.3318E+02: 612924 element volumes b/w 0.3318E+02 and 0.6605E+02: 54612 element volumes b/w 0.6605E+02 and 0.1315E+03: 18204 element volumes b/w 0.1315E+03 and 0.2617E+03: 45510 element volumes b/w 0.2617E+03 and 0.5210E+03: 63714 element volumes b/w 0.2617E+03 and 0.5210E+03: 63714 min volume = 1.6666667E+01 max volume = 5.2100000E+02 ----------------------------------------------------------- 794964 total elements evaluated.
Example call and report from the quality command with no arguments.