The naco_spc_combine recipe



Combination of spectroscopic science data


naco_spc_combine – NACO Combination of spectroscopic science data.

The files listed in the Set Of Frames (sof-file) must be tagged: NACO-raw-file.fits SPEC_NODDING or NACO-flat-file.fits MASTER_SPC_FLAT (optional).

For nodded frames (SPEC_NODDING) there must be an identical number of exposures on each side of the center, these pairs of nodded exposures should preferably be taken with one immediately after the other. More precisely, the i’th A-FRAME will be paired with the i’th B-frame



Create an object for the recipe naco_spc_combine.

import cpl
naco_spc_combine = cpl.Recipe("naco_spc_combine")



Stop the spectrum extraction at this column (int; default: 1024) [default=1024].


Start the spectrum extraction at this column (int; default: 1) [default=1].

A positive value causes additional, intermediate products to be saved (int; default: 0) [default=0].


The recipe can produce a number of predefined plots. Zero means that none of the plots are produced, while increasing values (e.g. 1 or 2) increases the number of plots produced. If the plotting fails a warning is produced, and the recipe continues. The default behaviour of the plotting is to use gnuplot (with option -persist). The recipe currently produces 1D-plots using gnuplot commands. The recipe user can control the actual plotting-command used by the recipe to create the plot by setting the environment variable CPL_PLOTTER. Currently, if CPL_PLOTTER is set it must contain the string ‘gnuplot’. Setting it to ‘cat > my_gnuplot_$$.txt’ causes a number of ASCII-files to be created, which each produce a plot when given as standard input to gnuplot (e.g. later or on a different computer). A finer control of the plotting options can be obtained by writing an executable script, e.g., that executes gnuplot after setting the desired gnuplot options (e.g. set terminal pslatex color) and then setting CPL_PLOTTER to The predefined plots include plotting of images. Images can be plotted not only with gnuplot, but also using the pnm format. This is controlled with the environment variable CPL_IMAGER. If CPL_IMAGER is set to a string that does not contain the word gnuplot, the recipe will generate the plot in pnm format. E.g. setting CPL_IMAGER to ‘display - &’ will produce a gray-scale image using the image viewer display. (int; default: 0) [default=0].

The following code snippet shows the default settings for the available parameters.

import cpl
naco_spc_combine = cpl.Recipe("naco_spc_combine")

naco_spc_combine.param.xtmax = 1024
naco_spc_combine.param.xtmin = 1 = 0
naco_spc_combine.param.plot = 0

You may also set or overwrite some or all parameters by the recipe parameter param, as shown in the following example:

import cpl
naco_spc_combine = cpl.Recipe("naco_spc_combine")
res = naco_spc_combine( ..., param = {"xtmax":1024, "xtmin":1})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

Please report any problems to Lars Lundin. Alternatively, you may send a report to the ESO User Support Department.