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diff --git a/web/content/docs/tools/model-preparation/convert-data-array-to-data-array/index.pandoc b/web/content/docs/tools/model-preparation/convert-data-array-to-data-array/index.pandoc
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++++
+date = "2018-12-17T10:56:57+01:00"
+title = "Convert vtk data array to another vtk data array"
+author = "Thomas Fischer"
+
+[menu]
+  [menu.tools]
+    parent = "model-preparation"
++++
+
+## General
+
+Often, meshes contain geometrical data in common with data used for process
+simulation. Usually, such data used by the process simulation is associated to
+the mesh nodes or to the mesh cells. In the vtk unstructured grid file format
+the geometrical and the process data information is stored in one file - in so
+called data arrays.
+
+Some tools, for instance paraview, export data arrays always using a floating
+point data type. OpenGeoSys expects the 'MaterialIDs' cell data array to have
+int data-type.
+
+Other tools, for instance Gocad, export data associated with cells or nodes
+sometimes as float. The tool can convert the cell data arrays to double
+data-type.
+
+## Usage
+
+```
+convertVtkDataArrayToVtkDataArray
+    --in-mesh <file name>
+    --existing-property-name <name of the cell data array as string>
+    --out-mesh <filename for the output mesh>
+    --new-property-name <name of the new cell data array>
+    --new-property-data-type <data type as string>
+```
+
+## Example
+
+```
+convertVtkDataArrayToVtkDataArray
+    -i doubleValuedMaterialIDs.vtu
+    -e MaterialIDs_double
+    --new-property-data-type int
+    -n MaterialIDs
+    -o intValuedMaterialIDs.vtu
+```
+
+::: {.note}
+### Example Files
+[doubleValuedMaterialIDs.vtu](doubleValuedMaterialIDs.vtu)
+:::