GrismGGrismG - The grating ruling density

Description:
This attribute holds the number of grating rulings per unit length. The unit of length used should be consistent with the units used for attributes GrismWaveRGrismWaveR and GrismNRPGrismNRP. The default value is 0.0. (the appropriate value for a pure prism disperser with no grating).
Type:
Double precision.
Class Applicability:
GrismMapGrismMap
All GrismMaps have this attribute.