| Allowed Value | Details | 
|---|---|
| McStas | the axis is referenced to the NeXus/HDF5 McStas laboratory Cartesian coordinate system | 
| abstract | the axis is referenced to an abstract Cartesian coordinate system | 
| direct | the axis is referenced to the direct lattice | 
| laboratory | the axis is referenced to the imgCIF standard laboratory Cartesian coordinate system | 
| orthogonal | the axis is referenced to the cell Cartesian orthogonal coordinates | 
| reciprocal | the axis is referenced to the reciprocal lattice | 
| Allowed Value | Details | 
|---|---|
| McStas | the axis is referenced to the NeXus/HDF5 McStas laboratory Cartesian coordinate system | 
| abstract | the axis is referenced to an abstract Cartesian coordinate system | 
| direct | the axis is referenced to the direct lattice | 
| laboratory | the axis is referenced to the imgCIF standard laboratory Cartesian coordinate system | 
| orthogonal | the axis is referenced to the cell Cartesian orthogonal coordinates | 
| reciprocal | the axis is referenced to the reciprocal lattice |