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diff --git a/noao/onedspec/doc/sys/onedv210.ms b/noao/onedspec/doc/sys/onedv210.ms new file mode 100644 index 00000000..431c84f5 --- /dev/null +++ b/noao/onedspec/doc/sys/onedv210.ms @@ -0,0 +1,680 @@ +.nr PS 9 +.nr VS 11 +.de LS +.RT +.if \\n(1T .sp \\n(PDu +.ne 1.1 +.if !\\n(IP .nr IP +1 +.if \\n(.$-1 .nr I\\n(IR \\$2n +.in +\\n(I\\n(IRu +.ta \\n(I\\n(IRu +.if \\n(.$ \{\ +.ds HT \&\\$1 +.ti -\\n(I\\n(IRu +\\*(HT +.br +.. +.ND +.TL +ONEDSPEC/IMRED Package Revisions Summary: IRAF Version 2.10 +.AU +Francisco Valdes +.AI +IRAF Group - Central Computer Services +.K2 +P.O. Box 26732, Tucson, Arizona 85726 +May 1992 +.NH +Introduction +.LP +The IRAF NOAO spectroscopy software, except for the \fBlongslit\fR +package, has undergone major revisions. The revisions to the aperture +extraction package, \fBapextract\fR, are described in a separate +document. This paper addresses the revisions in the \fBonedspec\fR +package and the spectroscopic image reduction packages in the +\fBimred\fR package. In addition to the revisions summary given here +there is a new help topic covering general aspects of the new +\fBonedspec\fR package such as image formats, coordinate systems, and +units. This help topic is referenced under the name +"onedspec.package". +.LP +There are a large number of revisions both minor and major. To avoid +obscuring the basic themes and the major revisions in a wealth of minor +detail, this document is organized into sections of increasing detail. The +most important aspects of the revisions are described in a major highlight +section followed by a minor highlight section. Then a reorganization chart +for the \fBonedspec\fR package is presented showing where various +tasks have been moved, which have been deleted, and which are new. +Finally, a summary of the revisions to each task is presented. +.LP +I hope that the many new capabilities, particularly as presented in the +highlight section, will outweigh any disruption in accomodating to so +many changes. +.NH +Major Highlights +.LP +The major highlights of the revisions to the NOAO spectroscopy software +are listed and then discussed below. + +.DS +\(bu Non-linear dispersion calibration +\(bu Integration of dispersion coordinates with the core system +\(bu Sinc interpolation +\(bu Plotting in user selected units including velocity +\(bu Integration of long slit spectra and 1D formats +\(bu New \fBimred\fR packages featuring streamlined reductions +.DE + +Possibly the most significant revision is the generalization allowing +non-linear dispersion calibration. What this means is that spectra do +not need to be interpolated to a uniform sampling in wavelength or +logarithmic wavelength. The dispersion functions determined from +calibration arc lines by \fBidentify\fR, \fBreidentify\fR, +\fBecidentify\fR, or \fBecreidentify\fR can be simply assigned to the +spectra and used throughout the package. It is also possible to assign +a dispersion table or vector giving the wavelengths at some or all of +the pixels. Note, however, that it is still perfectly acceptible to +resample spectra to a uniform linear or log-linear dispersion as was +done previously. +.LP +For data which does not require geometric corrections, combining, or +separate sky subtraction the observed sampling need never be changed +from the original detector sampling, thus avoiding any concerns over +interpolation errors. In other cases it is possible to just +interpolate one spectrum, say a sky spectrum, to the dispersion of +another spectrum, say an object spectrum, before operating on the two +spectra. There are several new tasks that perform interpolations to a +common dispersion, not necessarily linear, when operating on more than +one spectrum. In particular, the new task \fBsarith\fR and the older +task \fBsplot\fR now do arithmetic on spectra in wavelength space. +Thus, one no longer need be concerned about having all spectra +interpolated to the same sampling before doing arithmetic operations as +was the case previously. +.LP +The trade-off in using non-linear dispersion functions is a more complex +image header structure. This will make it difficult to import to non-IRAF +software or to pre-V2.10 IRAF systems. However, one may resample to a +linear coordinate system in those cases before transfering the spectra as +FITS images having standard linear coordinate keywords. +.LP +On the subject of interpolation, another important addition is the +implementation of sinc interpolation. This is generally considered +the best interpolation method for spectra, however, it must be used +with care as described below. +Sinc interpolation approximates applying a phase shift to the fourier +transform of the spectrum. Thus, repeated interpolations do not accumulate +errors (or nearly so) and, in particular, a forward and reverse +interpolation will recover the original spectrum much more closely than +other interpolation methods. However, for undersampled (where the fourier +transform is no longer completely represented), strong features, such as +cosmic rays or narrow emission or absorption lines, the ringing can be much +more severe than the polynomial interpolations. The ringing is especially +a concern because it extends a long way from the feature causing the +ringing; 30 pixels with the truncated algorithm that has been added. Note +that it is not the truncation of the interpolation function which is at +fault but the undersampling of the narrow features! +.LP +Because of the problems seen with sinc interpolation it should be used with +care. Specifically, if there are no undersampled, narrow features it is a +good choice but when there are such features the contamination of the +spectrum by ringing is more severe, corrupting more of the spectrum, +than with other interpolation types. +.LP +The dispersion coordinates are now interfaced through the IRAF WCS +(world coordinate system) interface. This is important to users for +two reasons. First, operations performed on spectral images by IRAF +core system tasks and the IRAF image I/O system will have access to the +dispersion coordinates and will properly modify them as necessary. The +most common such operation is applying an image section to a spectrum +either during an image copy or as input to another task. In this case +the relation between the pixels in the image section and their +wavelengths is preserved. For example one may \fBsplot\fR a section of +a large spectrum and get the correct wavelengths. The second reason is +to allow use of proper dispersion coordinates in such IRAF tasks as +\fBlistpixels\fR, \fBimplot\fR, and \fBgraph\fR. +.LP +The new package supports a variety of spectral image formats. The +older formats are understood when reading them. In particular the one +dimensional "onedspec" and the two dimensional "multispec" format will +still be acceptable as input. Note that the image naming syntax for +the "onedspec" format using record number extensions is a separate +issue and is still provided but only in the \fBimred.iids\fR and +\fBimred.irs\fR packages. Any new spectra created are either a one +dimensional format using relatively simple keywords and a two or three +dimensional format which treats each line of the image as a separate +spectrum and uses a more complex world coordinate system and keywords. +For the sake of discussion the two formats are still called "onedspec" +and "multispec" though they are not equivalent to the earlier formats. +.LP +In addition, the one dimensional spectral tasks may also now operate on +two dimensional images directly. This is done by using the DISPAXIS +keyword in the image header or a package dispaxis parameter if the +keyword is missing to define the dispersion axis. In addition there is +a summing parameter in the packages to allow summing a number of lines +or columns. If the spectra are wavelength calibrated long slit +spectra, the product of the \fBlongslit.transform\fR task, the +wavelength information will also be properly handled. Thus, one may +use \fBsplot\fR or \fBspecplot\fR for plotting such data without having +to extract them to another format. If one wants to extract one +dimensional spectra by summing columns or lines, as opposed to using +the more complex \fBapextract\fR package, then one can simply use +\fBscopy\fR (this effectively replaces \fBproto.toonedspec\fR). +.LP +The tasks \fBsplot\fR and \fBspecplot\fR allow use of and changes +between various dispersion units. Spectra may be plotted in units all +the way from Hertz to Mev. The units may also be inverted to plot in +wavenumbers, such as inverse centimeters, and the decimal log may be +applied, to plot something like log wavelength or log frequency. One +special "unit" which is available is a velocity computed about a +specified wavelength/frequency. The multiple unit capability was one +of the last major changes made before the V2.10 release so the complete +generalization to arbitrary units has not been completed. Dispersion +calibration and image world coordinate system generally must still be +done in Angstroms, particularly if flux calibration is to be done. The +generalization to other units throughout the package is planned for a +later release. +.LP +The last of the changes catagorized as a major highlight is the +addition of a number of special packages for generic or specific +types of instruments and data in the \fBimred\fR package. Most of these +package include a highly streamlined reduction task that combines +all of the reduction operations into a single task. For example, +the \fBspectred.doslit\fR task can extract object, standard star, and +arc spectra from long slit images, apply a consistent dispersion +function based on only a single interactively performed dispersion +solution, compute a sensitivity function and end up with flux +calibrated spectra. Another example, is \fBhydra.dohydra\fR for +extracting, flatfielding, dispersion calibrating, and sky subtracting +spectra from the NOAO Hydra multifiber spectrograph. There are user's +guides for each of these new reduction tasks. +.NH +Minor Highlights +.LP +There are some further highlights which are also quite important +but which are secondary to the previous highlights. These are listed +and discussed below. + +.DS +\(bu Greater use of package parameters +\(bu An observatory database +\(bu A more flexible \fBidentify/reidentify\fR +\(bu Only one \fBdispcor\fR +\(bu Spatial interpolation of dispersion solutions +\(bu Deblending of arbitrary number of gaussian components +\(bu Manipulating spectral formats +\(bu Improved fitting of the continuum and related features +\(bu Various new tasks +.DE + +There is an even greater use of package parameters than in the previous +release. Package parameters are those which are common to many of the +the tasks in the package and which one usually wants to change in +one place. The new package parameters are the default observatory for +the data if the observatory is not identified in the image header +(discussed further below), the interpolation type used +when spectra need to be resampled either for dispersion calibration +or when operating on pairs of spectra with different wavelength +calibration, and the default dispersion axis and summing parameters +for long slit and general 2D images (as discussed in the last section). +You will find these parameters not only in the \fBonedspec\fR package but in +all the spectroscopic packages in the \fBimred\fR package. +.LP +A number of spectroscopic tasks require information about the location +of the observation. Typically this is the observatory latitude for +computing air masses if not defined in the header. Radial velocity +tasks, and possible future tasks, may require additional information +such as longitude and altitude. The difficulty is that if such +parameters are specified in parameter files the default may well be +inappropriate and even if the users set then once, they may forget to +update them in later reductions of data from a different observatory. +In other words this approach is prone to error. +.LP +To address this concern observatory parameters are now obtained from an +observatory database keyed by an observatory identifier. If the image data +contains an observatory keyword, OBSERVAT, the tasks will look up the +required parameters from the observatory database. Thus, if the images +contain the observatory identifier, as does data from the NOAO +observatories, they will always be correctly reduced regardless of the +setting of any parameters. Of course one has to deal with data from +observatories which may not include the observatory identifier and may not +have an entry in the observatory database. There are provisions for sites +and individual users to define local database files and to set the default +observatory parameters. This is all discussed in the help for the +\fBobservatory\fR task. +.LP +The dispersion function fitting tasks \fBidentify\fR and +\fBreidentify\fR have been improved in a number of important ways. +These tasks now treat the input images as units. So for long slit and +multispectrum images one can move about the image with a few +keystrokes, transfer solutions, and so on. When transfering solutions +between a multispectrum reference image and another multispectrum image +with the same apertures using \fBreidentify\fR, the features and +dispersion solutions are transfered aperture by aperture. This avoids +problems encountered by having to trace successively between apertures +and having the apertures be in the same order. +.LP +On the subject of tracing in \fBreidentify\fR, in some cases it is +desirable to use the same reference spectrum with all other sampled +lines or columns in a long slit spectrum or apertures in a +multispectrum image rather than propagating solutions across the +image. The latter method is necessary if there is a continuous and +progress shift in the features. But if this is not the situation then +the loss of features when tracing can be a problem. In this case the +alternative of reidentifying against the same starting reference is now +possible and there will not be the problem of an increasing loss of +features. On the other hand, the problem of lost features, whether +tracing or not, can also be addressed using another new feature of +\fBreidentify\fR, the ability to add features from a line list. For +both tracing and nontracing reidentifications, another useful new +feature is automatic iterative rejection of poorly fitting lines in +determining a new dispersion function noninteractively. +.LP +The nontracing reidentifications, the automatic addition of new lines, and +the iterative rejection of poorly fitting lines in determining a new +dispersion function are all responses to make the reidentification process +work better without intervention. However, as a last resort there is also +a new interactive feature of \fBreidentify\fR. By monitoring the log output of +the reidentification process one can have a query be made after the +automatic reidentification and function fitting to allow selectively +entering the interactive feature identification and dispersion function +fitting based on the logged output. Thus if a fit has a particularly large +RMS or a large number of features are not found one can chose to intervene +in the reidentification process. +.LP +Dispersion calibration is now done exclusively by the task +\fBdispcor\fR regardless of the spectrum format or dispersion solution +type; i.e. solutions from \fBidentify\fR or \fBecidentify\fR. In addition to +allowing assignment of non-linear dispersion functions, as described +earlier, \fBdispcor\fR has other new features. One is that, in +addition to interpolating dispersion solutions between two calibration +images (usually weighted by time), it is now possible to interpolate +zero point shifts spatially when multiple spectra taken simultaneously +include arc spectra. This is mostly intended for the new generation of +multifiber spectrographs which include some fibers assigned to an arc +lamp source. However, it can be used for the classic photographic case +of calibration spectra on the same plate. +.LP +The limitation to four lines on the number of gaussian components which +can be deblended by the deblending option in \fBsplot\fR has been removed. +A new feature is that line positions may be input from a line list as +well as the original cursor marking or terminal input. +In addition an option to simultaneously determine a linear background +has been added. As a spinoff of the deblending option a new, noninteractive +task, called FITPROFS, has been added. This task takes a list of initial +line positions and sigmas and simultaneously fits gaussians with a +linear background. One can constrain various combination of parameters +and output various parameters of the fitting. While it can be used to +fit an entire spectrum it becomes prohibitively slow beyond a number like +30. A banded matrix approach is required in that case. +.LP +As mentioned earlier there is a new task called \fBscopy\fR for manipulating +spectra. It allows changing between various formats such as producing +the separate, simple keyword structure, one dimensional images from multispec +format images, combining multiple one dimensional spectra into the +more compact multispec format, and extracting line or column averaged one +dimensional spectra from two dimensional images. It can also be +used to select any subset of apertures from a multispec format, +merge multiple multispec format spectra, and extract regions of spectra +by wavelength. +.LP +The \fBcontinuum\fR task has been revised to allow independent +continuum fits for each aperture, order, line, or column in images +containing multiple spectra. Instead of being based on the +\fBimages.fit1d\fR task it is based on the new task \fBsfit\fR. +\fBSfit\fR allows fitting the \fBicfit\fR functions to spectra and +outputing the results in several ways such as the ratio (continuum +normalization), difference (continuum subtraction), and the actual +function fit. In addition it allows outputing the input data with +points found to be deviant by the iterative rejection algorithm of +\fBicfit\fR replaced by the fitted value. This is similar to +\fBimages.lineclean\fR. In all cases, this is may be done +independently and interactively or noninteractively when there are +multiple spectra in an image. +.LP +A number of useful new tasks have already been mentioned: +\fBfitprofs\fR, \fBsarith\fR, \fBscombine\fR, \fBscopy\fR, and +\fBsfit\fR. There are two more new tasks of interest. The task \fBdopcor\fR +applies doppler shifts to spectra. It applies the shift purely to the +dispersion coordinates by adding a redshift factor which is applied by +the coordinate system interface. This eliminates reinterpolation and +preserves both the shift applied and the original observed dispersion +function (either linear or nonlinear). The task can also modify the +pixel values for various relativistic and geometric factors. This task +is primarily useful for shifting spectra at high redshifts to the local +rest frame. The second new task is called \fBderedden\fR. It applies +corrections for interstellar reddening given some measure of the +extinction along the line of site. +.NH +ONEDSPEC Package Task Reorganization +.LP +The \fBonedspec\fR package dates back to the earliest versions of IRAF. Some of +its heritage is tied to the reduction of IRS and IIDS spectra. One of +the revisions made for this release has been to reorganize the various +tasks and packages. A few tasks have been obsoleted by new tasks or +the functionality of the new dispersion coordinate system, a number +of new tasks have been added, and a number of IRS and IIDS specific +tasks have been moved to the \fBimred\fR packages for those instruments. +While these packages are organized for those particular instruments they may +also be used by data having similar characteristics of beam switching, +coincidence corrections, and the requirement of sequential numeric +extensions. +.LP +The table below provides the road map to the reorganization showing +tasks which have disappeared, been moved, been replaced, or are new. + +.DS +.TS +center; +r l l l r l l. +V2.9 V2.10 ALTERNATIVE V2.9 V2.10 ALTERNATIVE + +addsets irs/iids process irs/iids +batchred irs/iids rebin scopy/dispcor +bplot bplot refspectra refspectra +bswitch irs/iids reidentify reidentify +calibrate calibrate sapertures +coincor iids sarith +combine scombine scombine +continuum continuum scopy + deredden sensfunc sensfunc +dispcor dispcor setdisp hedit + dopcor sextract scopy + fitprofs sfit +flatdiv irs/iids sflip scopy/imcopy [-*,*] +flatfit irs/iids shedit hedit +identify identify sinterp sinterp +lcalib lcalib slist slist +mkspec mkspec specplot specplot +names names splot splot + ndprep standard standard +observatory noao subsets irs/iids +powercor iids sums irs/iids +.TE +.DE +.NH +IMRED Packages +.LP +Many of the \fBonedspec\fR tasks from the previous release have been +moved to the \fBiids\fR and \fBirs\fR packages, as indicated above, +since they were applicable only to these and similar instruments. +.LP +A number of new specialized spectroscopic instrument reduction packages +have been added to the \fBimred\fR package. Many of these have been in +use in somewhat earlier forms in the IRAF external package called +\fBnewimred\fR. In addition the other spectroscopic package have been +updated based on the revisions to the \fBonedspec\fR and +\fBapextract\fR packages. Below is a table showing the changes between +the two version and describing the purpose of the spectroscopic +packages. Note that while many of these package are named for and +specialized for various NOAO instruments these packages may be applied +fairly straightforwardly to similar instruments from other +observatories. In addition the same tools for multifiber and slit +spectra are collected in a generic package called \fBspecred\fR. + +.DS +.TS +center; +r l l s +r l l l. +V2.9 V2.10 SPECTROSCOPY PACKAGE + argus Fiber: CTIO Argus Reductions +specphot ctioslit Slit: CTIO Slit Instruments +echelle echelle Fiber Slit: Generic Echelle + hydra Fiber: KPNO Hydra (and Nessie) Reductions +iids iids Scanner: KPNO IIDS Reductions +irs irs Scanner: KPNO IRS Reductions +coude kpnocoude Fiber/Slit: KPNO Coude (High Res.) Reductions + kpnoslit Slit: KPNO Slit Instruments +msred specred Fiber/Slit: Generic fiber and slit reductions +observatory -> noao +setairmass +.TE +.DE +.LP +An important feature of most of the spectroscopic packages are specialized +routines for combining and streamlining the different reduction operations +for a particular instrument or type of instrument. These tasks are: + +.DS +.TS +center; +r r r. +argus.doargus ctioslit.doslit echelle.doecslit +echelle.dofoe hydra.dohydra iids.batchred +irs.batchred kpnocoude.do3fiber kpnocoude.doslit +kpnoslit.doslit specred.dofibers specred.doslit +.TE +.DE +.NH +ONEDSPEC Task Revisions in V2.10 +.LS ADDSETS 2 +Moved to the \fBiids/irs\fR packages. +.LS BATCHRED +Moved to the \fBiids/irs\fR packages. +.LS BPLOT +The APERTURES and BAND parameters been added to select +apertures from multiple spectra and long slit images, and bands +from 3D images. Since the task is a script calling \fBsplot\fR, the +many revisions to that task also apply. The version in the +\fBiids/irs\fR packages selects spectra using the record number +extension syntax. +.LS BSWITCH +Moved to the \fBiids/irs\fR packages. +.LS CALIBRATE +This task was revised to operate on nonlinear dispersion +corrected spectra and 3D images (the \fBapextract\fR "extras"). The +aperture selection parameter was eliminated (since the header +structure does not allow mixing calibrated and uncalibrated +spectra) and the latitude parameter was replaced by the +observatory parameter. The observatory mechanism insures that +if the observatory latitude is needed for computing an airmass +and the observatory is specified in the image header the +correct calibration will be applied. The record format syntax +is available in the \fBiids/irs\fR packages. The output spectra are +coerced to have real pixel datatype. +.LS COINCOR +Moved to the \fBiids\fR package. +.LS COMBINE +Replaced by \fBscombine\fR. +.LS CONTINUUM +This task was changed from a script based on \fBimages.fit1d\fR to a +script based on \fBsfit\fR. This provides for individual independent +continuum fitting in multiple spectra images and for additional +flexibility and record keeping. The parameters have been +largely changed. +.LS DEREDDEN +This task is new. +.LS DISPCOR +This is a new version with many differences. It replaces the +previous three tasks \fBdispcor\fR, \fBecdispcor\fR and \fBmsdispcor\fR. It +applies both one dimensional and echelle dispersion functions. +The new parameter LINEARIZE selects whether to interpolate the +spectra to a uniform linear dispersion (the only option +available previously) or to assign a nonlinear dispersion +function to the image without any interpolation. The +interpolation function parameter has been eliminated and the +package parameter INTERP is used to select the interpolation +function. The new interpolation type "sinc" may be used but +care should be exercised. The new task supports applying a +secondary zero point shift spectrum to a master dispersion +function and a spatial interpolation of the shifts when +calibration spectra are taken at the same time on a different +region of the same 2D image. The optional wavelength table may +now also be an image to match dispersion parameters. The +APERTURES and REBIN parameters have been eliminated. If an +input spectrum has been previously dispersion corrected it will +be resampled as desired. Verbose and log file parameters have +been added to log the dispersion operations as desired. The +record format syntax is available in the \fBiids/irs\fR packages. +.LS DOPCOR +This task is new. +.LS FITPROFS +This task is new. +.LS FLATDIV +Moved to the \fBiids/irs\fR packages. +.LS FLATFIT +Moved to the \fBiids/irs\fR packages. +.LS IDENTIFY +The principle revision is to allow multiple aperture images and +long slit spectra to be treated as a unit. New keystrokes +allow jumping or scrolling within multiple spectra in a single +image. For aperture spectra the database entries are +referenced by image name and aperture number and not with image +sections. Thus, \fBidentify\fR solutions are not tied to specific +image lines in this case. There is a new autowrite parameter +which may be set to eliminate the save to database query upon +exiting. The new colon command "add" may be used to add +features based on some other spectrum or arc type and then +apply the fit to the combined set of features. +.LS LCALIB +This task has a more compact listing for the "stars" option and +allows paging a list of stars when the star name query is not +recognized. +.LS MKSPEC +This task is unchanged. +.LS NAMES +This task is unchanged. +.LS NDPREP +This task was moved from the \fBproto\fR package. It was originally +written at CTIO for CTIO data. It's functionality is largely +unchanged though it has been updated for changes in the +\fBonedspec\fR package. +.LS OBSERVATORY +New version of this task moved to \fBnoao\fR root package. +.LS POWERCOR +Moved to the \fBiids\fR package. +.LS PROCESS +Moved to the \fBiids/irs\fR package. +.LS REBIN +This task has been eliminated. Use \fBscopy\fR or \fBdispcor\fR. +.LS REFSPECTRA +A group parameter was added to allow restricting assignments by +observing period; for example by night. The record format +option was removed and the record format syntax is available in +the \fBiids/irs\fR packages. +.LS REIDENTIFY +This task is a new version with many new features. The new +features include an interactive options for reviewing +identifications, iterative rejection of features during +fitting, automatic addition of new features from a line list, +and the choice of tracing or using a single master reference +when reidentifying features in other vectors of a reference +spectrum. Reidentifications from a reference image to another +image is done by matching apertures rather than tracing. New +apertures not present in the reference image may be added. +.LS SAPERTURES +This task is new. +.LS SARITH +This task is new. +.LS SCOMBINE +This task is new. +.LS SCOPY +This task is new. +.LS SENSFUNC +The latitude parameter has been replaced by the observatory +parameter. The 'i' flux calibrated graph type now shows flux +in linear scaling while the new graph type 'l' shows flux in +log scaling. A new colon command allows fixing the flux limits +for the flux calibrated graphs. +.LS SETDISP +This task has been eliminated. Use \fBhedit\fR or the package +DISPAXIS parameter. +.LS SEXTRACT +Replaced by \fBscopy\fR. +.LS SFIT +This task is new. +.LS SFLIP +This task has been eliminated. Use image sections. +.LS SHEDIT +This task has been eliminated. Use \fBhedit\fR if needed. +.LS SINTERP +This task is unchanged. +.LS SLIST +This task was revised to be relevant for the current spectral +image formats. The old version is still available in the +\fBiids/irs\fR package. +.LS SPECPLOT +New parameters were added to select apertures and bands, plot +additional dimensions (for example the additional output from +the extras option in \fBapextract\fR), suppress the system ID banner, +suppress the Y axis scale, output a logfile, and specify the +plotting units. The PTYPE parameter now allows negative +numbers to select histogram style lines. Interactively, the +plotting units may be changed and the 'v' key allows setting a +velocity scale zero point with the cursor. The new version +supports the new spectral WCS features including nonlinear +dispersion functions. +.LS SPLOT +This is a new version with a significant number of changes. In +addition to the task changes the other general changes to the +spectroscopy packages also apply. In particular, long slit +spectra and spectra with nonlinear dispersion functions may be +used with this task. The image header or package dispaxis and +nsum parameters allow automatically extracting spectra from 2D +image. The task parameters have been modified primarily to +obtain the desired initial graph without needing to do it +interactively. In particular, the new band parameter selects +the band in 3D images, the units parameter selects the +dispersion units, and the new histogram, nosysid, and xydraw +options select histogram line type, whether to include a system +ID banner, and allow editing a spectrum using different +endpoint criteria. +.LS +Because nearly every key is used there has been some shuffling, +consolidating, or elimination of keys. One needs to check the +run time '?' help or the help to determine the key changes. +.LS +Deblending may now use any number of components and +simultaneous fitting of a linear background. A new simplified +version of gaussian fitting for a single line has been added in +the 'k' key. The old 'k', 'h', and 'v' equivalent width +commands are all part of the single 'h' command using a second +key to select a specific option. The gaussian line model from +these modes may now be subtracted from the spectrum in the same +way as the gaussian fitting. The one-sided options, in +particular, are interesting in this regard as a new capability. +.LS +The arithmetic functions between two spectra are now done in +wavelength with resampling to a common dispersion done +automatically. The 't' key now provides for the full power of +the ICFIT package to be used on a spectrum for continuum +normalization, subtraction, or line and cosmic ray removal. +The 'x' editing key may now use the nearest pixel values rather +than only the y cursor position to replace regions by straight +line segments. The mode is selected by the task option +parameter "xydraw". +.LS +Control over the graph window (plotting limits) is better +integrated so that redrawing, zooming, shifting, and the \fBgtools\fR +window commands all work well together. The new 'c' key resets +the window to the full spectrum allowing the 'r' redraw key to +redraw the current window to clean up overplots from the +gaussian fits or spectrum editing. +.LS +The dispersion units may now be selected and changed to be from +hertz to Mev and the log or inverse (for wave numbers) of units +taken. As part of the units package the 'v' key or colon +commands may be used to plot in velocity relative to some +origin. The $ key now easily toggles between the dispersion +units (whatever they may be) and pixels coordinates. +.LS +Selection of spectra has become more complex with multiaperture +and long slit spectra. New keys allow selecting apertures, +lines, columns, and bands as well as quickly scrolling through +the lines in multiaperture spectra. Overplotting is also more +general and consistent with other tasks by using the 'o' key to +toggle the next plot to be overplotted. Overplots, including +those of the gaussian line models, are now done in a different +line type. +.LS +There are new colon commands to change the dispersion axis and +summing parameters for 2D image, to toggle logging, and also to +put comments into the log file. +.LS STANDARD +Giving an unrecognized standard star name will page a list of +standard stars available in the calibration directory and then +repeat the query. +.LS SUBSETS +Moved to the \fBiids/irs\fR packages. +.LS SUMS +Moved to the \fBiids/irs\fR packages. |