Griding and spectra cube visualization

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Griding and spectra cube visualization

The functionalities of the old `ANALYSE\GRID` command has been redistributed and extended in several commands:

- `ANALYSE\TABLE` creates a table containing the offsets, weights and intensities of all the dumped spectra. A check of the consistency of the observations in the current index is performed at this step, if not already done before.
- `MAP\XY_MAP` grids the dumped spectra from the table to an lmv cube. An image of the associated weights is also produced for further processing like optimal combination of several data cubes.
- Moreover, all the plotting capabilities of GREG program has been imported inside CLASS so that the user can directly visualize the data cube of the gridded spectra. For instance, Fig. has been obtained with the following sequence of commands:

                LAS90> file in 12co21-newfmt.30m
                LAS90> find
                LAS90> table 12co21 new
                LAS90> xy_map 12co21
                LAS90> let name 12co21
                LAS90> let type lmv
                LAS90> go view

  The “go view” scripts enables interactive visualization of a spectra cube. Channel maps may be produced through the go bit command and position-velocity diagrams through the go xv and go vy commands.

Figure: Screen-shot of result of the go view command. The top,left panel is the channel map corresponding to velocity shown as a vertical red line in the top,right panel. The top,right panel displays the spectrum at the position localized on the top,right panel. The bottom,left panel shows the line emission integrated over the velocity range appearing in yellow on the bottom,right panel. This last panel displays the spectrum averaged over the whole map. go view is an interactive command with many more features. Please, type h to display the complete help.