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+.. _devguide_voxel:
+
+=====================================
+Voxel Plot Binary File Specifications
+=====================================
+
+----------
+Revision 1
+----------
+
+**integer(4) n_voxels_x**
+
+    Number of voxels in the x direction
+
+**integer(4) n_voxels_y**
+
+    Number of voxels in the y direction
+
+**integer(4) n_voxels_z**
+
+    Number of voxels in the z direction
+
+**real(8) width_voxel_x**
+
+    Width of voxels in the x direction
+
+**real(8) width_voxel_y**
+
+    Width of voxels in the y direction
+
+**real(8) width_voxel_z**
+
+    Width of voxels in the z direction
+
+**real(8) lower_left_x**
+
+    Lower left x point of the voxel grid
+
+**real(8) lower_left_y**
+
+    Lower left y point of the voxel grid
+
+**real(8) lower_left_z**
+
+    Lower left z point of the voxel grid
+
+*do x = 1, n_voxels_x*
+    *do y = 1, n_voxels_y*
+        *do z = 1, n_voxels_z*
+
+            **integer(4) id**
+
+                Cell or material id number at this voxel center. Set to -1 when
+                cell not_found.