How do I plot stacked spectra?

The DATACUBE package provides two tasks to carry out this process, the stacker (see the figure) and multistack shell scripts.

Figure: The stacker script.

A run of the stacker script is shown below.

   % stacker
   NDF input file: ifu_file
 
         Input NDF:
           File: ifu_file.sdf
         Shape:
           No. of dimensions: 3
           Dimension size(s): 59 x 110 x 961
           Pixel bounds     : 1:59, 1:110, 1:961
           Total pixels     : 6236890
         Collapsing:
           White-light image: 59 x 110
 
   Number of spectra: 3
 
     Left click on pixel to be extracted.
 
         Extracting:
           (X,Y) pixel: 24,80
 
     Left click on pixel to be extracted.
 
         Extracting:
           (X,Y) pixel: 30,71
 
     Left click on pixel to be extracted.
 
         Extracting:
           (X,Y) pixel: 30,55
 
   Offset: 200
 
         Adding:
           Adding 0 to spectrum 1
           Adding 200 to spectrum 2
           Adding 400 to spectrum 3
 
         Plotting:
           Spectrum: 3 
           Spectrum: 2 
           Spectrum: 1 
 
   Zoom in (yes/no): yes
 
     Left click on lower zoom boundary.
     Left click on upper zoom boundary.
 
         Zooming:
           Lower Boundary: 6792.26
           Upper Boundary: 7745.58
 
         Plotting:
           Spectrum: 3
           Spectrum: 2
           Spectrum: 1
   %

Here we extract three spectra by clicking on a white-light image of the data cube, and these are then plotted with an offset of 200 counts between each spectrum. We then get the opportunity to zoom into a region of interest, and the three spectra are then re-plotted.

The multistack script operates in a similar manner, however, here we are prompted for the number of spectral groups required, and the number of spectra in each group. The mean spectrum of for each `group' of spectra is calculated, and then all the mean spectra are plotted in a stack as before, as seen in the following example.

   % multistacker
   NDF input file: ifu_file
 
         Input NDF:
           File: ifu_file.sdf
         Shape:
           No. of dimensions: 3
           Dimension size(s): 59 x 110 x 961
           Pixel bounds     : 1:59, 1:110, 1:961
           Total pixels     : 6236890
         Collapsing:
           White-light image: 59 x 110
  
   Number of groups: 3
 
   Number of spectra in group: 4
  
     Left click on pixel to be extracted.
                .
                .
                .

Here we request three groups of four spectra each, i.e. we'll get three mean spectra plotted as a stack in the final display.