Thanks for the help.<br><br>1. I tried to figure out but it seems to be a little bit beyond me.<br>Given the directions I will try to fix the problem myself and maybe then I will submit my first patch to vtk!<br><br>2. I can confirm that the node orders for quad9/bi-quadratic-quad are identical. <br>
So when quadratic quad is used instead of bi-quadratic quad, the missing node is the last one (8).<br><br>3 -- 6 -- 2<br>| | |<br>7 -- 8 -- 5<br>| | |<br>0 -- 4 -- 1<br><br>However, one question is how does vtkExodusIIReader<br>
differe from vtkExodusReader.<br>If I open the file and use PrintSelf methods They produce slightly different information:<br><br>vtkExodusIIReader:<br><b><br>Debug: Off<br>Modified Time: 34<br>Reference Count: 2<br>Registered Events: (none)<br>
Executive: 0x1536d60<br>ErrorCode: Success<br>Information: 0x1533ed0<br>AbortExecute: Off<br>Progress: 1<br>Progress Text: (None)<br>FileName: sphere-6.exo<br>XMLFileName: (null)<br>DisplayType: 0<br>TimeStep: 0<br>TimeStepRange: [0, 0]<br>
ExodusModelMetadata: OFF<br>PackExodusModelOntoOutput: ON<br>ExodusModel: 0<br>Metadata:<br> Exoid: -1<br> AppWordSize: 8<br> DiskWordSize: 8<br> ExodusVersion: 4.57<br> ModelParameters:<br> Title: cubit(/home/dansari/Desktop/sphere-6.exo): 05/13/2011: 16:08:57<br>
Dimension: 3<br> Nodes: 26<br> Edges: 0<br> Faces: 0<br> Elements: 6<br> Edge Blocks: 0<br> Face Blocks: 0<br> Element Blocks: 1<br> Node Sets: 0<br> Edge Sets: 0<br> Face Sets: 0<br> Side Sets: 0<br>
Element Sets: 0<br> Node Maps: 0<br> Edge Maps: 0<br> Face Maps: 0<br> Element Maps: 0<br> Time steps (0):<br> TimeStep: 0<br> HasModeShapes: 0<br> ModeShapeTime: -1<br> Blocks:<br> Element block 1 "Unnamed block ID: 1 Type: QUAD9 Size: 6" (6)<br>
FileOffset: 1<br> CachedConn: 0x153b380 (1)<br> PointMap: 26 entries, ReversePointMap: 26 entries<br> Type: QUAD9<br> Bounds per entry, Node: 9 Edge: 0 Face: 0<br> Attributes (0):<br>
Sets:<br> Maps:<br> Array Cache:<br> Debug: Off<br> Modified Time: 10<br> Reference Count: 1<br> Registered Events: (none)<br> Capacity: 128 MiB<br> Size: 0.00390625 MiB<br> Cache: 0x1536d10 (4)<br>
LRU: 0x1536d40<br> SqueezePoints: 1<br> ApplyDisplacements: 1<br> DisplacementMagnitude: 1<br> GenerateObjectIdArray: 1<br> GenerateFileIdArray: 0<br> FileId: 0</b><br><br><br>ExdosuReader:<br><br><b><br>Modified Time: 85<br>
Reference Count: 2<br>Registered Events: (none)<br>Executive: 0x2310390<br>ErrorCode: Success<br>Information: 0x2307ed0<br>AbortExecute: Off<br>Progress: 1<br>Progress Text: (None)<br>GenerateBlockIdCellArray: On<br>GenerateGlobalElementIdArray: On<br>
GenerateGlobalNodeIdArray: On<br>PackExodusModelOntoOutput: On<br>ApplyDisplacements: On<br>ExodusModelMetadata: Off<br>File Name: sphere-6.exo<br>XML File Name: (none)<br>Title: cubit(/home/dansari/Desktop/sphere-6.exo): 05/13/2011: 16:08:57<br>
Dimensionality: 3<br>NumberOfUsedNodes: 20<br>NumberOfNodesInFile: 26<br>NumberOfUsedElements: 6<br>NumberOfElementsInFile: 6<br>NumberOfBlocks: 1<br> 6 elements in block 1<br>NumberOfTimeSteps: 0<br>NumberOfPointArrays: 0<br>
NumberOfCellArrays: 0<br>NumberOfSideSets: 0<br>NumberOfNodeSets: 0<br>TimeStep: 0<br>TimeStepRange: 0 -1<br>DisplacementMagnitude: 1<br>DisplayType: 1<br>HasModeShapes: 0<br></b><br>The output from ExodusIIReader clearly suggests that my elements are 9 node quads!<br>
<br>Please advise<br><br>Davood<br><br><br><div class="gmail_quote">On Fri, May 13, 2011 at 12:02 PM, David Thompson <span dir="ltr"><<a href="mailto:dcthomp@sandia.gov">dcthomp@sandia.gov</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Hi Davood,<br>
<br>
The ExodusII reader was created before VTK had Soeren Gebbert's 9-node quadratic elements, so the 8-node quad was used as an approximation. It appears that vtkExodusIIReaderPrivate::DetermineVtkCellType needs to be changed to use the bi-quadratic quad, but there may be more depending on the order nodes are specified in by Exodus vs. VTK (see vtkExodusIIReader::GetCacheOrRead around line 2225 for what's done with hexahedra).<br>
<br>
If someone wants to create a patch, I'll be happy to review it in Gerrit.<br>
<br>
David<div><div></div><div class="h5"><br>
<br>
On May 12, 2011, at 9:17 , Davood Ansari wrote:<br>
<br>
</div></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div><div></div><div class="h5">
Hi all<br>
<br>
I am having some trouble with reading ExodusII files generated from Cubit 12.<br>
The elements are supposed to be (and based from what I see in the .exo file are)<br>
biqudratic quads that have 9 points. When I read the file using vtkExodusIIReader,<br>
however, I get quadratic quads with 8 sampling points.<br>
<br>
Any idea what is going one?<br>
<br>
Attached is the header for my .exo mesh file, as you see num_nod_per_el1 = 9 ; but I still get 8 point quadratic quad in VTK??<br>
<br>
<br>
netcdf sphere {<br>
dimensions:<br>
len_string = 33 ;<br>
len_line = 81 ;<br>
four = 4 ;<br>
time_step = UNLIMITED ; // (0 currently)<br>
num_dim = 3 ;<br>
num_nodes = 386 ;<br>
num_elem = 96 ;<br>
num_el_blk = 1 ;<br>
num_qa_rec = 1 ;<br>
num_el_in_blk1 = 96 ;<br>
num_nod_per_el1 = 9 ;<br>
variables:<br>
double time_whole(time_step) ;<br>
char qa_records(num_qa_rec, four, len_string) ;<br>
char coor_names(num_dim, len_string) ;<br>
char eb_names(num_el_blk, len_string) ;<br>
int elem_map(num_elem) ;<br>
int eb_status(num_el_blk) ;<br>
int eb_prop1(num_el_blk) ;<br>
eb_prop1:name = "ID" ;<br>
int connect1(num_el_in_blk1, num_nod_per_el1) ;<br>
connect1:elem_type = "QUAD9" ;<br>
double coord(num_dim, num_nodes) ;<br>
<br>
// global attributes:<br>
:api_version = 4.57f ;<br>
:version = 4.57f ;<br>
:floating_point_word_size = 8 ;<br>
:file_size = 0 ;<br>
:title = "cubit(/home/dansari/Desktop/sphere/sphere.exo): 03/22/2011: 19:24:22" ;<br>
<br></div></div>
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