[vtkusers] Interpolation of data..

[Rakesh Patil]

 sorry.. forgot to attach file..:)ThanksRegardsRakesh Patil Original message From:Bill Lorensen< bill.lorensen at gmail.com >Date: 24 Apr 10 18:15:33Subject:Re: [vtkusers] Interpolation of data..To: Rakesh Patil The last part of this example:http://www.vtk.org/Wiki/VTK/Examples/InterpolateTerraindoes what you want.Basically,1) Add the lat/log and elevations to a polydata2) Create a surface with Delaunay2D3) Add the points with unknown elevation to a vtkPoints4) Use a cell locator to cast infinite rays into the surface to findthe elevation.On Fri, Apr 23, 2010 at 9:50 PM, Rakesh Patilwrote:>>> Well,>> I was trying with this example:>> http://www.vtk.org/Wiki/VTK/Examples/InterpolateTerrain>> In this example, there are two ways specified for interpolation.. One is> using> vtkProbeFilter and another is using vtkCellLocator>> First i tried using vtkProbeFilter. But failed getting the output.. But> using the> vtkCellLocator, i was able to produce interpolated values for the third> co
 lumn of MeshG.>> After observation, i foound that only the region which is common in both the> grids,> was interpolated. So i was fully stuck wondering how to find the remaining> values..>> any comments..??>> Thanks>> Rakesh Patil>>  Original message > From:"Dean Inglis"< dean.inglis at camris.ca >> Date: 23 Apr 10 23:59:48> Subject: Re: Re:[vtkusers]Interpolation of data..> To: "Rakesh Patil">> How can you expect your mesh to get interpolated> when its z coordinate values are all 0> but the scatter data range in z from 700 to 900?> The bounds of each unstructured grid do not even> overlap / intersect!>> Dean>>> Hi,My both the meshes are unstructured grid. My application is based on>> FEA method.. ScatterG does contains scalars and the depth values are>> stored as a scalar array for scatterG..I dont want coordinate values to be>> interpolated.. As an example,scatterG contains data something like>> this,Points: 87.23 16.2690086.24 17.8753087.18 17.27700......and the>> scalar for
  scatterG is defined as 900530700......meshG contains>> points84.1217.83 081.3315.28 083.2418.28 0......So,, what i want to do is,>> using the third column of scatterG, i need to estimate the third column of>> meshG..Any ideas how it can be done.??ThanksRakesh Patil Original message>> From:"De an Inglis"< dean.inglis at camris.ca >Date: 23 Apr 10>> 20:16:47Subject:Re: Re:[vtkusers]Interpolation of data..To: "Rakesh Patil">> vtkProbeFlter will probe the scalar values ateach spatial location of your>> scattered points: youneed to have scalar, vector, or tensor data>> associatedwith the grid's points:scatterG>GetPointData()>SetScalars(>> somevt>> kDataArray );the vtkProbeFilter will not interpolate any coordinatevalues>> like x , y,z locations.If you have depth valuesin a vtkDataArray that>> correspond to the x, y, z locationsin your scatterG grid, then this should>> work.Does anyone know ifmaybe the input to the probe filter needs to be a>> structured data set likevtkPolyData? By
  the sound of your grid's name>> "mesh" , this sounds like structureddata.Can it be converted to a>> vtkPolyData?Also, you allocate a smart pointer as:vtkSmartPointer probe =>> vtkSmartPointer: :New()Dean Original Message From: "Rakesh Patil" To: Cc:>> Sent: Friday, April 23, 2010 9:40 AMSubject: Re: Re:[vtkusers]>> Interpolation of data..> Hi..I can independently view those grids... This>> is what I have done..vtkUnstructuredGrid *scatterG =>> MyApp::getInstance()>getScatterGrid();vtkUnstructuredGrid *meshG =>> MyApp::getInstance()>getMeshGrid();vtkSmartPointer probe =>>>> vtkSmartPointer::New();probe>SetSource(scatterG);probe>SetInput(meshG);probe>Update();vtkDataArr>> ay *data = probe>GetOutput()>GetPointData()>GetScalar();vtkDoubleArray>> *doubleArray =>>>> vtkDoubleArray::SafeDownCast(data);MyContour::getInstance()>setDisplayArray(doubleArray);After>> doing this, i click on contour display button, and the contour for>> bathymetry gets displayed for meshG.Initially, mesh
 G doesnt have>> depth/elevation (z) value. z value is always 0 for every node point. x and>> y corresponds to the lon and lat respectively.But the scatter data>> contains lon, lat, and depth.. So, once the interpolation is done, i>> should get the bathymetry (depth/elevation) for meshG also..'MyContour' in>> the above code is the class which displays the contours for wh> atever>> data is being passed.So, any suggestions or > comments..??ThanksRegards>> Rakesh Patil Original messageFrom:Dean Inglis< > dean.inglis at camris.ca >>> Date: 23 Apr 10 16:49:50 Subject:Re: > Re:[vtkusers]Interpolation of>> data.. To: "Rakesh Patil">>>>>> > Powered by www.kitware.com>> Visit other Kitware opensource projects at> http://www.kitware.com/opensource/opensource.html>> Please keep messages ontopic and check the VTK FAQ at:> http://www.vtk.org/Wiki/VTKFAQ>> Follow this link to subscribe/unsubscribe:> http://www.vtk.org/mailman/listinfo/vtkusers>> 
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