IMPORT/EXPORT : file conversion
Principles
As you may guess, with this tool, a single spectrum maybe extracted
as a 1D image from a given datacube. But it may also be used to export
simultaneously ALL the spectra from a given datacube rearranged in a
2D image.
Use
- Click on [Import/Export] in the main menu,
then on [Export spectra from
datacube]. The [Export spectra from datacube] pops up.
- Enter the name of the Input datacube.
You can type it in directly, or use the browse
icon at the end of the field, or drag and drop it from the
Reduction
folder.
- Enter the name of the Output object,
which will be either a
single spectrum (a 1D image) or a 2D image holding all the spectra
from the datacube, according to the user's choice.
Parameters
- Spectrum identification : the user may choose :
- Single lens (#) : a single spectrum will be extracted,
stored into a 1D file, and the user is requested to identify
this spectrum by its lens number.
- Single lens (arcsec) : a single spectrum will be
extracted,
stored into a 1D file, and the user is requested to identify
this spectrum by its (approximate) relative [Alpha,Delta]
position on the sky;
remember that [0,0] is the center of the field.
- Single lens (CCD) : a single spectrum will be extracted,
stored into a 1D file, and the user is requested to identify
this spectrum by its approximate CCD pixel coordinates.
- Single lens (columns) : a single spectrum will be
extracted,
stored into a 1D file, and the user is requested to identify
this spectrum by the values which are to be found in two columns
[X label] and [Y label]
in the mother table associated with the datacube.
- 2D output, and a 2D image is created, where [x] is
the lambda coordinate, and where each spectrum occupies a line of
the image. The spatial field is explored starting from the lower
left corner, and a line of lenses is followed to its upper end.
These lines are the ones which are tilted ~6 degrees relative to
CCD columns on a micropupil image.
Each lens (spectrum) found on this line of lenses is written in
the image above the preceding one. Once at the end (top) of the
line, the process is repeated with the line of lenses which is
next to the right, and so on until all the field has been covered.
So, each lenses column gives a strip in the output image. In this
strip, spectra are spatially correlated. Optionally (recommended)
spectra strips maybe separated in the image by a black (zero) line.
This tool is provided to give ARGUS user's a more familiar
touch-and-feel... A table is created, too, to hold the
{N,X,Y} triplets, that is the coordinates of the lens
N which produced the Nth spectrum,
or the Nth line of the image. It is named after the name the
user gives for the output object, by adding the prefix string
tab_ and changing the extension from .tig to
.fits. The user is asked to give the
labels [X label] and [Y label] of the columns which hold,
in the mother table associated with the input datacube,
the coordinates he whishes to keep track of.
Options
- Options : you have the choice of checking Spectrum
(and the spectrum itself is recorded; this is the default),
S/N (and the S/N ratio
spectrum is recorded), or Noise (and the noise spectrum is
recorded).
- Debug : this switches the program to verbose mode, and
more informations are recorded into the history file
(see button [Start] in the left menu).
- Save values :
All the input values (files names, etc...) are saved,
and become the new default values for this user. They can
be recalled at will, and are used each time the Export
spectrum from datacube window is opened.
- Recall values :
The values saved by the user,
are loaded to the various input fields.
- Default values :
The input fields are set to the general defaults values;
for instance, the file names are set to blank.
Principles
This feature is provided to allow the user to reimport into a datacube
the spectra he exported from another datacube as a 2D image using
function [Export spectrum from datacube] (see preceding paragraph).
The idea is that the exported 2D image has been worked on using some
external package, and is now ready to be reimported to continue with
XOasis reduction process.
Use
- Click on [Import/Export] in the main menu,
then on [Import spectra into datacube]. This window pops up.
- Enter the name of the Input 2D image, the associated
Input table, and of the Output datacube.
- Click on [Accept].
Parameters
- Input 2D image : this is the image which has been built
using the
Export spectra from datacube function, option
[All spectra]. No other input format is supported.
You can type the name in directly, or use the browse
icon at the end of the field, or drag and drop it from the
Reduction
folder.
- Input table : this is the name of the table, holding the
spatial information, which has been automatically created at the same
time as the 2D image; it was named tab_{name-of-the-2D-image}.
But it may be any table as long as it holds the right information in
the right place.
Same input possibilities.
- Output datacube : the name of the new datacube which will be
created using the 2D image and table data. Same input possibilities.
- Input type : in release 4.3, there is only one possibility,
that is 2D input; so, do not mind...
- X label, Y label : the labels of the table columns which
are to be taken as the coordinates for the reconstruction of the
datacube from the 2D image. It is usually [A,D], but it may change
if the user worked on the table to perform some coordinate
transformation, creating new columns.
Options
- Debug : this switches the program to verbose mode, and
more informations are recorded into the history file
(see button [Start] in the left menu).
- Save values :
All the input values (files names, etc...) are saved,
and become the new default values for this user. They can
be recalled at will, and are used each time the Import
spectra into datacube window is opened.
- Recall values :
The values saved by the user,
are loaded to the various input fields.
- Default values :
The input fields are set to the general defaults values;
for instance, the file names are set to blank.
Principles
This tools allows the user to convert to and from MIDAS, IRAF, ASCII FITS
and binary FITS format.
Use
- Click on [Import/Export] in the main menu, then on [File exchange].
The [File exchange] window pops up.
- Enter the name of the Input file,
and of the Output file.
You can type them in directly, or use the browse
icons at the end of the field, or drag and drop them from the
Reduction
folder.
- Choose the Input format and the Output format.
- Click on [Accept].
Optional parameters
- Save values :
All the input values (files names, etc...) are saved,
and become the new default values for this user. They can
be recalled at will, and are used each time the Convert file
format window is opened.
- Recall values :
The values saved by the user,
are loaded to the various input fields.
- Default values :
The input fields are set to the general defaults values;
for instance, the file names are set to blank.
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Last update: 11/01/1999. Send comments to
martin@cfht.hawaii.edu