NASVD Menu

This menu initiates the NASVD processing of the multichannel spectra. The processing outputs are:

• the NASVD eigenvectors, which are stored in a binary file in the working directory alongside the database, and 
• the NASVD eigenvector amplitudes, which are stored as a new multi-band field in the database.

The input multi-channel spectra are not adjusted in any way. The NASVD processing can take a while, and eigenvectors can be viewed at a later time using the View NASVD Eigenvectors tool (View|View NASVD Eigenvectors).

The Nasvd analysis is applied to around 20,000 – 50,000 (or more) spectra at a time. The spectra are grouped for processing using a group-by field – either a Nasvd Group or a Nasvd Cluster. Nasvd Groups are created using the Create Group-By Field tool (Utilities|Create Group-By Field). Nasvd Clusters are created using the Create Spectra Cluster Field (Utilities|Create Spectra Cluster Field).