Our algorithm to produce the short-spacing information is coded in the magentaUV_SHORT command. magentaUV_SHORT will add the short spacing information to the current uv table (read by command magentaREAD UV and optionally transformed by further magenta UV_... processing commands).
magentaUV_SHORT has a substantial number (17) of control variables, but with experience, they have been reduced to 5 significant ones, among which only 3 really matter in most cases but often can be used with their default values:
magentaUV_SHORT ? will list these 3 major ones, and magentaUV_SHORT ?? the 2 remaining main ones:
The magentaUV_SHORT command starts from data in a the format produced by the red CLASS command TABLE command, and read in [rgb]1,0,0IMAGER through command magentaREAD SINGLE. Basically, this is a GDF table containing one line per spectrum, the columns representing the lambda offset, beta offset, weight, and the spectrum intensities. 6. This data must match spectrally the velocity sampling of the interferometric data. This can be obtained using the magenta/RESAMPLING option of command magentaTABLE in red CLASS.
The magentaREAD SINGLE and magentaUV_SHORT commands also support a 3-D data cube (as produced by e.g. command magentaXY_MAP in red CLASS) as input instead of a red CLASS table. Again, the velocity axis must match that of the interferometric data.
magentaUV_SHORT will automatically produce the Zero spacing from the single-dish data when the data does not allow other short spacings to be evaluated. The temporary image produced by magentaUV_SHORT when starting from a red CLASS Table is stored in the magentaSHORT buffer, and can be written by command magentaWRITE. This image can aslo be computed separately by command magentaXY_SHORT.
Finally, as magentaUV_SHORT adds the
short spacing information, magentaUV_SHORT /REMOVE allows to remove
it (there is no direct ``replace'' possibility because the sampling
may change).
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Gildas manager
2023-06-01