# Cell Modify

- Symmetry
- Type
- Position
- Origin
- View

Change here the position and orientation of the cell (or list of cells, previously selected with Cell->Select, when Global is pressed). Parameters for empty entries or Local choices remain unchanged.

### Translation

The origin of a cell object, defined by its (0 0 0) node, can be changed using the X, Y, Z entries.

By default, in Conventional, Primitive and Parallelepiped volumes, this node is at a corner of the cell volume, in a Sphere volume it is at the center, and in a Wigner volume it is at the center of the first Wigner-Seitz cell.

To define exactly the cell translation, relatively to other cell or relatively to the current layer, press Align.

### Rotation

The orientation of a cell object, defined by the Euler angles theta, phi, psi, can be changed using the E1, E2, E3 entries.

Euler angles in GAMGI are defined as follows: first, the (x, y, z) referential is rotated theta degrees (between 0 and 180) around the y axis, then the referential is rotated phi degrees (between 0 and 360) around the initial z axis, and finally it is rotated psi degrees (between 0 and 360) around the new z axis, always in the direct, counter-clockwise, direction. If the first Euler angle (theta) is zero, the old and new z axis coincide, thus (0, 0, 10) and (0, 5, 5) represent the same rotation.

By default, the first conventional vector is aligned with the x axis (even if conventional vectors are not actually represented), the second vector is in the xy plane and the third vector has a positive z coordinate (pointing to the user), corresponding to Euler angles (0, 0, 0).

The cell orientation is independent of the volume representation. This way, conventional, primitive and Wigner-Seitz cells can be easily compared, as they have the same orientation.

To define exactly the cell rotation, relatively to other cell or relatively to the current layer, press Align.
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