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diff --git a/noao/onedspec/doc/rspectext.hlp b/noao/onedspec/doc/rspectext.hlp new file mode 100644 index 00000000..2973f552 --- /dev/null +++ b/noao/onedspec/doc/rspectext.hlp @@ -0,0 +1,138 @@ +.help rspectext Oct93 onedspec +.ih +NAME +rspectext -- convert 1D ascii text spectra to IRAF image spectra +.ih +USAGE +rspectext input output +.ih +PARAMETERS +.ls input +Input list of ascii text spectra. These may have a optional FITS header +at the beginning and then two columns of wavelength and flux. +.le +.ls output +Output list of IRAF spectra image names. The list must match the +input list. +.le + + +The following parameters are only used if there is no FITS header +with the data. +.ls title = "" +Title to be assigned to the spectra. +.le +.ls flux = no +Are the flux values flux calibrated? If so then header keywords are +inserted to identify this for the IRAF spectral software. +.le +.ls dtype = "linear" (none|linear|log|nonlinear|interp) +Type of dispersion to assign to the spectra. The options are: +.ls none +No dispersion function and nothing is added to the image header. +.le +.ls linear +Store the linear dispersion parameters \fBcrval1\fR and \fBcdelt1\fR +in the image header. The wavelength values are ignored. This may +be used if the wavelength values are known to be linear but one wants +to avoid possible roundoff and resampling errors introduced by the +"interp" option. +.le +.ls log +Store the log-linear dispersion parameters \fBcrval1\fR and \fBcdelt1\fR in +the image header. The wavelength values are ignored. This may be used if +the wavelength values are known to be linear in the log of the wavelength +but one wants to avoid possible roundoff and resampling errors introduced +by the "interp" option. +.le +.ls nonlinear +Store the wavelength values in the image header as a lookup table. +The flux values are not resampled. The wavelength values need not +be evenly sampled. +.le +.ls interp +Use the wavelength values to resample to a linear dispersion between +the first and last wavelength values. The dispersion per pixel is +determined by the number of pixels and the endpoint wavelengths. +.le +.le +.ls crval1 = 1., cdelt1 = 1. +The wavelength coordinate of the first pixel and the wavelength interval +per pixel to be used with the linear and log dispersion types. +.le +.ih +DESCRIPTION +Ascii text files consisting of an optional FITS header (usually produced +by \fBwspectext\fR) and a two column list of wavelengths and fluxes +are converted to IRAF image spectra. If a header is included then +the header information is assumed to describe the spectra including +any dispersion function. If no header is given then the minimal +information for describing spectra in IRAF is added. The dispersion +function can be set either a linear or log-linear based on two +keywords (ignoring the wavelength values) or from the wavelength +values. The latter may be stored in the header as a lookup table +allowing for nonlinear dispersions or resample to a linear dispersion. +This task is a script based on \fBrtextimage\fR for the creating +the image and entering the flux values, \fBhedit\fR to set some +of the header keywords, and \fBdispcor\fR to handle the nonlinear +or resampled dispersion functions. +.ih +EXAMPLES +1. Create spectrum from a text file originally produced by \fBwspectext\fR. + +.nf + cl> type text001 + BITPIX = 8 / 8-bit ASCII characters + NAXIS = 1 / Number of Image Dimensions + NAXIS1 = 100 / Length of axis + ORIGIN = 'NOAO-IRAF: WTEXTIMAGE' / + IRAF-MAX= 0. / Max image pixel (out of date) + IRAF-MIN= 0. / Min image pixel (out of date) + IRAF-B/P= 32 / Image bits per pixel + IRAFTYPE= 'REAL FLOATING ' / Image datatype + OBJECT = 'TITLE ' / + FILENAME= 'TEST ' / IRAF filename + FORMAT = '5G14.7 ' / Text line format + APNUM1 = '1 1 ' + DC-FLAG = 0 + WCSDIM = 1 + CTYPE1 = 'LINEAR ' + CRVAL1 = 4000. + CRPIX1 = 1. + CDELT1 = 10.1010101010101 + CD1_1 = 10.1010101010101 + LTM1_1 = 1. + WAT0_001= 'system=equispec ' + WAT1_001= 'wtype=linear label=Wavelength units=Angstroms ' + END + + 4000.00 1000. + 4010.10 1005.54 + 4020.20 1011.05 + ... + cl> rspectext text001 spec001 +.fi + +2. Create a spectrum with a nonlinear dispersion using the wavelength +values as a lookup table. + +.nf + cl> type text002 + 4000.00 1000. + 4010.10 1005.54 + 4020.20 1011.05 + ... + cl> rspectext text002 spec002 title="HH12" dtype=nonlinear +.fi +.ih +REVISIONS +.ls RSPECTEXT V2.11 +The task now automatically senses the presence of a header. +.le +.ls RSPECTEXT V2.10.3 +This is a new task with this version. +.le +.ih +SEE ALSO +wspectext, rtextimage, dispcor, mkms, imspec, sinterp +.endhelp |