VTK image data is the appropriate type, not VTK rectilinear grid

FFTs require constant spacing in all three directions, this is
guaranteed by the vtkImageData but not by vtkRectilinearGrid

PRIVATE

@@ -1 +1 @@
-Subproject commit 4e63593fa25bbb296fc734c82aff3353190565f7
+Subproject commit 31d65b01e2b775b790d43ff78fd87a2d481f89c6

examples/grid/20grains16x16x16.vti

@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 16 0 16 0 16">
+  <ImageData WholeExtent="0 16 0 16 0 16" Origin="0 0 0" Spacing="0.0625 0.0625 0.0625" Direction="1 0 0 0 1 0 0 0 1">
     <FieldData>
       <Array type="String" Name="comments" NumberOfTuples="2" format="binary">
         AQAAAACAAAAkAAAALAAAAA==eF7LzUwuyi8uKSpNLiktSi1WMDJgyMjPzU9PzcusSizJzM/jNGQAAASkDSY=
@@ -14,17 +14,6 @@
         AQAAAACAAAAAAAAADwYAAA==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
       </DataArray>
     </CellData>
-    <Coordinates>
-      <DataArray type="Float64" Name="x" format="binary" RangeMin="0" RangeMax="1">
-        AQAAAACAAACIAAAAOAAAAA==eF5jYEAGG+wh9AEofQJKX4DSV6D0DSh9B0o/gNKPoPQTKP0MSr+A0q+g9Bso/Q5Kf7AHAB2kEak=
-      </DataArray>
-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="1">
-        AQAAAACAAACIAAAAOAAAAA==eF5jYEAGG+wh9AEofQJKX4DSV6D0DSh9B0o/gNKPoPQTKP0MSr+A0q+g9Bso/Q5Kf7AHAB2kEak=
-      </DataArray>
-      <DataArray type="Float64" Name="z" format="binary" RangeMin="0" RangeMax="1">
-        AQAAAACAAACIAAAAOAAAAA==eF5jYEAGG+wh9AEofQJKX4DSV6D0DSh9B0o/gNKPoPQTKP0MSr+A0q+g9Bso/Q5Kf7AHAB2kEak=
-      </DataArray>
-    </Coordinates>
   </Piece>
-  </RectilinearGrid>
+  </ImageData>
 </VTKFile>

examples/grid/tension-hold-unload.yaml

@@ -0,0 +1,37 @@
+solver: {mechanical: spectral_basic}
+
+loadstep:
+  - boundary_conditions:
+      mechanical:
+        P:
+          - [x, x, x]
+          - [x, 0, x]
+          - [x, x, 0]
+        dot_F:
+          - [0.001, 0, 0]
+          - [0, x, 0]
+          - [0, 0, x]
+    discretization: {t: 10.0, N: 40}
+    f_out: 4
+  - boundary_conditions:
+      mechanical:
+        dot_P:
+          - [0, x, x]
+          - [x, x, x]
+          - [x, x, x]
+        dot_F:
+          - [x, 0, 0]
+          - [0, 0, 0]
+          - [0, 0, 0]
+    discretization: {t: 10.0, N: 20}
+  - boundary_conditions:
+      mechanical:
+        P:
+          - [0, x, x]
+          - [x, 0, x]
+          - [x, x, 0]
+        dot_F:
+          - [x, 0, 0]
+          - [0, x, 0]
+          - [0, 0, x]
+    discretization: {t: 10.0, N: 20}

python/damask/_grid.py

@@ -8,7 +8,6 @@ import numpy as np
 import pandas as pd
 import h5py
 from scipy import ndimage, spatial
-from vtk.util.numpy_support import vtk_to_numpy as vtk_to_np
 
 from . import VTK
 from . import util
@@ -21,7 +20,7 @@ class Grid:
     Geometry definition for grid solvers.
 
     Create and manipulate geometry definitions for storage as VTK
-    rectiliear grid files ('.vtr' extension). A grid contains the
+    image data files ('.vit' extension). A grid contains the
     material ID (referring to the entry in 'material.yaml') and
     the physical size.
     """
@@ -153,12 +152,12 @@ class Grid:
     @staticmethod
     def load(fname):
         """
-        Load from VTK rectilinear grid file.
+        Load from VTK image data file.
 
         Parameters
         ----------
         fname : str or or pathlib.Path
-            Grid file to read. Valid extension is .vtr, which will be appended
+            Grid file to read. Valid extension is .vti, which will be appended
             if not given.
 
         Returns
@@ -167,15 +166,13 @@ class Grid:
             Grid-based geometry from file.
 
         """
-        v = VTK.load(fname if str(fname).endswith('.vtr') else str(fname)+'.vtr')
+        if str(fname).endswith('.vtr'):
+            warnings.warn('Support for vtr files will be removed in DAMASK 3.1.0', DeprecationWarning,2)
+        v = VTK.load(fname)
         comments = v.get_comments()
         cells = np.array(v.vtk_data.GetDimensions())-1
         bbox  = np.array(v.vtk_data.GetBounds()).reshape(3,2).T
 
-        for i,c in enumerate([v.vtk_data.GetXCoordinates(),v.vtk_data.GetYCoordinates(),v.vtk_data.GetZCoordinates()]):
-            if not np.allclose(vtk_to_np(c),np.linspace(bbox[0][i],bbox[1][i],cells[i]+1)):
-                raise ValueError('regular grid spacing violated')
-
         return Grid(material = v.get('material').reshape(cells,order='F'),
                     size = bbox[1] - bbox[0],
                     origin = bbox[0],
@@ -320,7 +317,7 @@ class Grid:
     @staticmethod
     def from_table(table,coordinates,labels):
         """
-        Generate grid from ASCII table.
+        Create grid from ASCII table.
 
         Parameters
         ----------
@@ -357,7 +354,7 @@ class Grid:
     @staticmethod
     def from_Laguerre_tessellation(cells,size,seeds,weights,material=None,periodic=True):
         """
-        Generate grid from Laguerre tessellation.
+        Create grid from Laguerre tessellation.
 
         Parameters
         ----------
@@ -413,7 +410,7 @@ class Grid:
     @staticmethod
     def from_Voronoi_tessellation(cells,size,seeds,material=None,periodic=True):
         """
-        Generate grid from Voronoi tessellation.
+        Create grid from Voronoi tessellation.
 
         Parameters
         ----------
@@ -494,7 +491,7 @@ class Grid:
     @staticmethod
     def from_minimal_surface(cells,size,surface,threshold=0.0,periods=1,materials=(0,1)):
         """
-        Generate grid from definition of triply periodic minimal surface.
+        Create grid from definition of triply periodic minimal surface.
 
         Parameters
         ----------
@@ -556,21 +553,21 @@ class Grid:
 
     def save(self,fname,compress=True):
         """
-        Save as VTK rectilinear grid file.
+        Save as VTK image data file.
 
         Parameters
         ----------
         fname : str or pathlib.Path
-            Filename to write. Valid extension is .vtr, it will be appended if not given.
+            Filename to write. Valid extension is .vti, it will be appended if not given.
         compress : bool, optional
             Compress with zlib algorithm. Defaults to True.
 
         """
-        v = VTK.from_rectilinear_grid(self.cells,self.size,self.origin)
+        v = VTK.from_image_data(self.cells,self.size,self.origin)
         v.add(self.material.flatten(order='F'),'material')
         v.add_comments(self.comments)
 
-        v.save(fname if str(fname).endswith('.vtr') else str(fname)+'.vtr',parallel=False,compress=compress)
+        v.save(fname if str(fname).endswith('.vti') else str(fname)+'.vti',parallel=False,compress=compress)
 
 
     def save_ASCII(self,fname):

python/damask/_result.py

@@ -527,7 +527,7 @@ class Result:
     def geometry0(self):
         """Initial/undeformed geometry."""
         if self.structured:
-            return VTK.from_rectilinear_grid(self.cells,self.size,self.origin)
+            return VTK.from_image_data(self.cells,self.size,self.origin)
         else:
             with h5py.File(self.fname,'r') as f:
                 return VTK.from_unstructured_grid(f['/geometry/x_n'][()],
@@ -1516,7 +1516,7 @@ class Result:
         Export to VTK cell/point data.
 
         One VTK file per visible increment is created.
-        For cell data, the VTK format is a rectilinear grid (.vtr) for
+        For cell data, the VTK format is a image data (.vti) for
         grid-based simulations and an unstructured grid (.vtu) for
         mesh-baed simulations. For point data, the VTK format is poly
         data (.vtp).

python/damask/_vtk.py

@@ -34,6 +34,36 @@ class VTK:
         self.vtk_data = vtk_data
 
 
+    @staticmethod
+    def from_image_data(cells,size,origin=np.zeros(3)):
+        """
+        Create VTK of type vtk.vtkImageData.
+
+        This is the common type for grid solver results.
+
+        Parameters
+        ----------
+        cells : iterable of int, len (3)
+            Number of cells along each dimension.
+        size : iterable of float, len (3)
+            Physical length along each dimension.
+        origin : iterable of float, len (3), optional
+            Coordinates of grid origin.
+
+        Returns
+        -------
+        new : damask.VTK
+            VTK-based geometry without nodal or cell data.
+
+        """
+        vtk_data = vtk.vtkImageData()
+        vtk_data.SetDimensions(*(np.array(cells)+1))
+        vtk_data.SetOrigin(*(np.array(origin)))
+        vtk_data.SetSpacing(*(size/cells))
+
+        return VTK(vtk_data)
+
+
     @staticmethod
     def from_rectilinear_grid(grid,size,origin=np.zeros(3)):
         """
@@ -167,6 +197,9 @@ class VTK:
             reader.SetFileName(str(fname))
             if dataset_type is None:
                 raise TypeError('Dataset type for *.vtk file not given.')
+            elif dataset_type.lower().endswith(('imagedata','image_data')):
+                reader.Update()
+                vtk_data = reader.GetImageDataOutput()
             elif dataset_type.lower().endswith(('rectilineargrid','rectilinear_grid')):
                 reader.Update()
                 vtk_data = reader.GetRectilinearGridOutput()
@@ -179,7 +212,9 @@ class VTK:
             else:
                 raise TypeError(f'Unknown dataset type {dataset_type} for vtk file')
         else:
-            if   ext == '.vtr':
+            if   ext == '.vti':
+                reader = vtk.vtkXMLImageDataReader()
+            elif ext == '.vtr':
                 reader = vtk.vtkXMLRectilinearGridReader()
             elif ext == '.vtu':
                 reader = vtk.vtkXMLUnstructuredGridReader()
@@ -213,7 +248,9 @@ class VTK:
             Compress with zlib algorithm. Defaults to True.
 
         """
-        if   isinstance(self.vtk_data,vtk.vtkRectilinearGrid):
+        if   isinstance(self.vtk_data,vtk.vtkImageData):
+            writer = vtk.vtkXMLImageDataWriter()
+        elif isinstance(self.vtk_data,vtk.vtkRectilinearGrid):
             writer = vtk.vtkXMLRectilinearGridWriter()
         elif isinstance(self.vtk_data,vtk.vtkUnstructuredGrid):
             writer = vtk.vtkXMLUnstructuredGridWriter()

python/damask/seeds.py

@@ -9,7 +9,7 @@ from . import grid_filters as _grid_filters
 
 def from_random(size,N_seeds,cells=None,rng_seed=None):
     """
-    Random seeding in space.
+    Place seeds randomly in space.
 
     Parameters
     ----------
@@ -43,7 +43,7 @@ def from_random(size,N_seeds,cells=None,rng_seed=None):
 
 def from_Poisson_disc(size,N_seeds,N_candidates,distance,periodic=True,rng_seed=None):
     """
-    Seeding in space according to a Poisson disc distribution.
+    Place seeds according to a Poisson disc distribution.
 
     Parameters
     ----------
@@ -96,7 +96,7 @@ def from_Poisson_disc(size,N_seeds,N_candidates,distance,periodic=True,rng_seed=
 
 def from_grid(grid,selection=None,invert=False,average=False,periodic=True):
     """
-    Create seed from existing grid description.
+    Create seeds from grid description.
 
     Parameters
     ----------

python/tests/reference/Grid/clean_1_1+2+3_False.vtr

@@ -1,25 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 8 0 5 0 4">
-  <Piece Extent="0 8 0 5 0 4">
-    <PointData>
-    </PointData>
-    <CellData>
-      <DataArray type="Int64" Name="materialpoint" format="binary" RangeMin="1" RangeMax="41">
-        AQAAAACAAAAABQAAYwAAAA==eF7t0scBgkAAAEHBgBEwgDmBsf8GfTANCN/bzzSwUa8pCrYyZp8DDjliwjEnnHLGORdMmTHnkiuuuWHBklvuuOeBR5545oVX3nhnxZoPPvnimx9+GQc7GT5sqvjvhz+ZtAcJ
-      </DataArray>
-    </CellData>
-    <Coordinates>
-      <DataArray type="Float64" Name="x" format="binary" RangeMin="0" RangeMax="0.000008">
-        AQAAAACAAABIAAAAOgAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2D3IeNxx9YfV6DiN+22x9tFGsbchco/sAMA/fQl6g==
-      </DataArray>
-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="0.000005">
-        AQAAAACAAAAwAAAAKwAAAA==eF5jYICAvrdbF3w/tsEOQh+wC30iUFisdRLKv2D3MeNxx9YfV+wAD5wZgw==
-      </DataArray>
-      <DataArray type="Float64" Name="z" format="binary" RangeMin="0" RangeMax="0.000004">
-        AQAAAACAAAAoAAAAIwAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2AHAFVBE/w=
-      </DataArray>
-    </Coordinates>
-  </Piece>
-  </RectilinearGrid>
-</VTKFile>

python/tests/reference/Grid/clean_1_1+2+3_True.vtr

@@ -1,25 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 8 0 5 0 4">
-  <Piece Extent="0 8 0 5 0 4">
-    <PointData>
-    </PointData>
-    <CellData>
-      <DataArray type="Int64" Name="materialpoint" format="binary" RangeMin="1" RangeMax="41">
-        AQAAAACAAAAABQAAYwAAAA==eF7t0scBgkAAAEHBgBEwgDmBsf8GfTANCN/bzzSwUa8pCrYyZp8DDjliwjEnnHLGORdMmTHnkiuuuWHBklvuuOeBR5545oVX3nhnxZoPPvnimx9+GQc7GT5sqvjvhz+ZtAcJ
-      </DataArray>
-    </CellData>
-    <Coordinates>
-      <DataArray type="Float64" Name="x" format="binary" RangeMin="0" RangeMax="0.000008">
-        AQAAAACAAABIAAAAOgAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2D3IeNxx9YfV6DiN+22x9tFGsbchco/sAMA/fQl6g==
-      </DataArray>
-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="0.000005">
-        AQAAAACAAAAwAAAAKwAAAA==eF5jYICAvrdbF3w/tsEOQh+wC30iUFisdRLKv2D3MeNxx9YfV+wAD5wZgw==
-      </DataArray>
-      <DataArray type="Float64" Name="z" format="binary" RangeMin="0" RangeMax="0.000004">
-        AQAAAACAAAAoAAAAIwAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2AHAFVBE/w=
-      </DataArray>
-    </Coordinates>
-  </Piece>
-  </RectilinearGrid>
-</VTKFile>

python/tests/reference/Grid/clean_1_1_False.vtr

@@ -1,25 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 8 0 5 0 4">
-  <Piece Extent="0 8 0 5 0 4">
-    <PointData>
-    </PointData>
-    <CellData>
-      <DataArray type="Int64" Name="materialpoint" format="binary" RangeMin="1" RangeMax="41">
-        AQAAAACAAAAABQAAYwAAAA==eF7t0scBgkAAAEHBgBEwgDmBsf8GfTANCN/bzzSwUa8pCrYyZp8DDjliwjEnnHLGORdMmTHnkiuuuWHBklvuuOeBR5545oVX3nhnxZoPPvnimx9+GQc7GT5sqvjvhz+ZtAcJ
-      </DataArray>
-    </CellData>
-    <Coordinates>
-      <DataArray type="Float64" Name="x" format="binary" RangeMin="0" RangeMax="0.000008">
-        AQAAAACAAABIAAAAOgAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2D3IeNxx9YfV6DiN+22x9tFGsbchco/sAMA/fQl6g==
-      </DataArray>
-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="0.000005">
-        AQAAAACAAAAwAAAAKwAAAA==eF5jYICAvrdbF3w/tsEOQh+wC30iUFisdRLKv2D3MeNxx9YfV+wAD5wZgw==
-      </DataArray>
-      <DataArray type="Float64" Name="z" format="binary" RangeMin="0" RangeMax="0.000004">
-        AQAAAACAAAAoAAAAIwAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2AHAFVBE/w=
-      </DataArray>
-    </Coordinates>
-  </Piece>
-  </RectilinearGrid>
-</VTKFile>

python/tests/reference/Grid/clean_1_1_True.vtr

@@ -1,25 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 8 0 5 0 4">
-  <Piece Extent="0 8 0 5 0 4">
-    <PointData>
-    </PointData>
-    <CellData>
-      <DataArray type="Int64" Name="materialpoint" format="binary" RangeMin="1" RangeMax="41">
-        AQAAAACAAAAABQAAYwAAAA==eF7t0scBgkAAAEHBgBEwgDmBsf8GfTANCN/bzzSwUa8pCrYyZp8DDjliwjEnnHLGORdMmTHnkiuuuWHBklvuuOeBR5545oVX3nhnxZoPPvnimx9+GQc7GT5sqvjvhz+ZtAcJ
-      </DataArray>
-    </CellData>
-    <Coordinates>
-      <DataArray type="Float64" Name="x" format="binary" RangeMin="0" RangeMax="0.000008">
-        AQAAAACAAABIAAAAOgAAAA==eF5jYICA3rdbF3w/tsEOQh+wC3kiUFisdRLKv2D3IeNxx9YfV6DiN+22x9tFGsbchco/sAMA/fQl6g==
-      </DataArray>
-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="0.000005">
-        AQAAAACAAAAwAAAAKwAAAA==eF5jYICAvrdbF3w/tsEOQh+wC30iUFisdRLKv2D3MeNxx9YfV+wAD5wZgw==
-      </DataArray>
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python/tests/reference/Grid/clean_1_None_False.vtr

@@ -1,25 +0,0 @@
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python/tests/reference/Grid/clean_1_None_True.vtr

@@ -1,25 +0,0 @@
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python/tests/reference/Grid/clean_2_1+2+3_False.vti

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+<?xml version="1.0"?>
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python/tests/reference/Grid/clean_2_1+2+3_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_2_1+2+3_True.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_2_1+2+3_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_2_1_False.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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+      </DataArray>
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python/tests/reference/Grid/clean_2_1_False.vtr

@@ -1,30 +0,0 @@
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-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_2_1_True.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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+  <Piece Extent="0 8 0 5 0 4">
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+    <CellData>
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python/tests/reference/Grid/clean_2_1_True.vtr

@@ -1,30 +0,0 @@
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-    <CellData>
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python/tests/reference/Grid/clean_2_2_False.vtr

@@ -1,25 +0,0 @@
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-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="1">
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-      <DataArray type="Float64" Name="z" format="binary" RangeMin="0" RangeMax="1">
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python/tests/reference/Grid/clean_2_2_True.vtr

@@ -1,25 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
-  <RectilinearGrid WholeExtent="0 20 0 18 0 8">
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-      <DataArray type="Float64" Name="y" format="binary" RangeMin="0" RangeMax="1">
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-  </RectilinearGrid>
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python/tests/reference/Grid/clean_2_None_False.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_2_None_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_2_None_True.vti

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+<?xml version="1.0"?>
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python/tests/reference/Grid/clean_2_None_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_1+2+3_False.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_3_1+2+3_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_1+2+3_True.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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+      </DataArray>
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python/tests/reference/Grid/clean_3_1+2+3_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_1_False.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+  <ImageData WholeExtent="0 8 0 5 0 4" Origin="0 0 0" Spacing="0.000001 0.0000010000000000000002 0.000001" Direction="1 0 0 0 1 0 0 0 1">
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+      </DataArray>
+    </CellData>
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+  </ImageData>
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python/tests/reference/Grid/clean_3_1_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_1_True.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_3_1_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_2_False.vtr

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python/tests/reference/Grid/clean_3_2_True.vtr

@@ -1,25 +0,0 @@
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python/tests/reference/Grid/clean_3_None_False.vti

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python/tests/reference/Grid/clean_3_None_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_3_None_True.vti

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+<?xml version="1.0"?>
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python/tests/reference/Grid/clean_3_None_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_1+2+3_False.vti

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python/tests/reference/Grid/clean_4_1+2+3_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_1+2+3_True.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_4_1+2+3_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_1_False.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_4_1_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_1_True.vti

@@ -0,0 +1,19 @@
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+  <Piece Extent="0 8 0 5 0 4">
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python/tests/reference/Grid/clean_4_1_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_2_False.vtr

@@ -1,25 +0,0 @@
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python/tests/reference/Grid/clean_4_2_True.vtr

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python/tests/reference/Grid/clean_4_None_False.vti

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python/tests/reference/Grid/clean_4_None_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/clean_4_None_True.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/clean_4_None_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/flip_directions_x-y-z.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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+      </DataArray>
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python/tests/reference/Grid/flip_directions_x-y-z.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/flip_directions_x.vti

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+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+  <ImageData WholeExtent="0 8 0 5 0 4" Origin="0 0 0" Spacing="0.000001 0.0000010000000000000002 0.000001" Direction="1 0 0 0 1 0 0 0 1">
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+      </DataArray>
+    </CellData>
+  </Piece>
+  </ImageData>
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python/tests/reference/Grid/flip_directions_x.vtr

@@ -1,30 +0,0 @@
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-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/flip_directions_y-z.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+  <ImageData WholeExtent="0 8 0 5 0 4" Origin="0 0 0" Spacing="0.000001 0.0000010000000000000002 0.000001" Direction="1 0 0 0 1 0 0 0 1">
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+  <Piece Extent="0 8 0 5 0 4">
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+    <CellData>
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+      </DataArray>
+    </CellData>
+  </Piece>
+  </ImageData>
+</VTKFile>

python/tests/reference/Grid/flip_directions_y-z.vtr

@@ -1,30 +0,0 @@
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-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/flip_directions_z-x-y.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+  <ImageData WholeExtent="0 8 0 5 0 4" Origin="0 0 0" Spacing="0.000001 0.0000010000000000000002 0.000001" Direction="1 0 0 0 1 0 0 0 1">
+    <FieldData>
+      <Array type="String" Name="comments" NumberOfTuples="1" format="binary">
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+      </Array>
+    </FieldData>
+  <Piece Extent="0 8 0 5 0 4">
+    <PointData>
+    </PointData>
+    <CellData>
+      <DataArray type="Int64" Name="material" format="binary" RangeMin="1" RangeMax="41">
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+      </DataArray>
+    </CellData>
+  </Piece>
+  </ImageData>
+</VTKFile>

python/tests/reference/Grid/flip_directions_z-x-y.vtr

@@ -1,30 +0,0 @@
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-<VTKFile type="RectilinearGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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-  <Piece Extent="0 8 0 5 0 4">
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python/tests/reference/Grid/get_grain_boundaries_8g12x15x20.vti

@@ -0,0 +1,19 @@
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+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/get_grain_boundaries_8g12x15x20.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/mirror_directions_x+reflect_False.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
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python/tests/reference/Grid/mirror_directions_x+reflect_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/mirror_directions_x-y-z+reflect_True.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/mirror_directions_x-y-z+reflect_True.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/mirror_directions_y-z+reflect_False.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/mirror_directions_y-z+reflect_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/mirror_directions_z-x-y+reflect_False.vti

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<VTKFile type="ImageData" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
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python/tests/reference/Grid/mirror_directions_z-x-y+reflect_False.vtr

@@ -1,30 +0,0 @@
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python/tests/reference/Grid/rotate_Eulers_0.0-32.0-240.0.vti

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python/tests/reference/Grid/rotate_Eulers_0.0-32.0-240.0.vtr

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python/tests/reference/Grid/rotate_Eulers_32.0-68.0-21.0.vti

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python/tests/reference/Grid/rotate_Eulers_32.0-68.0-21.0.vtr

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python/tests/reference/Grid/scale_grid_10-10-10.vti

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python/tests/reference/Grid/scale_grid_10-10-10.vtr

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python/tests/reference/Grid/scale_grid_10-11-10.vti

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python/tests/reference/Grid/scale_grid_10-11-10.vtr

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python/tests/reference/Grid/scale_grid_10-13-10.vti

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python/tests/reference/Grid/scale_grid_10-13-10.vtr

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python/tests/reference/Grid/scale_grid_10-20-2.vti

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python/tests/reference/Grid/scale_grid_10-20-2.vtr

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python/tests/reference/Grid/scale_grid_5-4-20.vti

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python/tests/reference/Grid/scale_grid_5-4-20.vtr

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python/tests/reference/Grid/scale_grid_8-10-12.vti

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python/tests/reference/Grid/scale_grid_8-10-12.vtr

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python/tests/reference/Result/12grains6x7x8.vti

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python/tests/reference/Result/12grains6x7x8.vtr

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python/tests/reference/Result/4grains2x4x3.vti

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python/tests/reference/Result/4grains2x4x3.vtr

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python/tests/reference/Result/6grains6x7x8_single_phase.vti

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python/tests/reference/Result/6grains6x7x8_single_phase.vtr

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python/tests/reference/Result/save_VTK/test_vtk[0-0-0].md5

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python/tests/reference/Result/save_VTK/test_vtk[0-0-1].md5

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