Iris Bugs & Caveats

o Specview, the GUI for Iris, can read both SEDs and spectra from files. If a spectrum is read in, the GUI does not plot error bars on the spectrum; errrors are plotted on loaded SED data, as we expected users to be interested in SEDs.

o Spectral coordinate errors are ignored if present in the input SED data.

o If two SEDs are read into Iris, and then models are fit to each SED, then the two SEDs cannot be coplotted. The user can only display one SED (with model) or the other. After closing the fit window, the user can again coplot the two SEDs.

o Certain actions, such as clicking on the data-to-model ratio plot after a fit, can cause the plot to be redrawn when the user did not mean to do so, giving the plot a flickering effect. (This flickering effect does seem to go away entirely when the user hides the ratio plot.)

o The name of the SED in the SED plot is automatically restored when switching from the Iris main window to the fit window (even if the user had removed the name from the plot). The opposite action, switching from the fit window back to the main window, does not produce any change in the SED plot.

o Iris fits in photon-flux density (photons/sec/cm^2/angstrom) and the best-fit parameters values will always be in terms of Angstroms, regardless of the user-defined unit settings.

o Model components which are deleted in the Fit -> Component window, are not removed automatically from the model expression.

o A model fit does not persist in the data display if the Fit dialog is dismissed.

o In the main window, the user can display either SED fluxes, or errors on fluxes, versus spectral coordinate. While the user displays errors, the "Fit" button is grayed out, because the user should fit a model to the fluxes, not to the error bars themselves. (Although the error bars are used in the fit.) The "Fit" button should be removed altogether when this plot is displayed. (To fit, the user should go back to displaying SED fluxes, and then click on "Fit".)

o In the Fit-> Edit window, there is a button labeled "Apply". This button is superfluous; user changes are accepted as soon as the user clicks return or tab.

o When the user feeds Iris a data file that includes NaNs as data points, Iris can apparently read and display the data, but clicking "Fit" could cause Iris to freeze, and require a restart.

o Both SEDImporter and Iris can write VOTables. If the user checks these files with xmllint and the IVOA VOTable v1.1 schema, the output VOTables will fail to validate.

o When NED returns only a single photometric data point in response to a user query, Iris cannot handle the resulting data set. Iris needs a SED to have a minimum of two photometric data points.

o SEDImporer and Iris can write FITS files as output, with NaNs written as numerical keyword values. If the user runs the HEASARC online FITS validator on a file containing NaNs as numerical keyword values, the validator will report failure.

o It may occasionally happen that the user must force Iris to quit, such as by using the "Force Quit" option from the Apple menu on a Mac, or the 'kill' command in a terminal window on Linux or Mac. Then the next time Iris is started, the user is unable to fit. The reason is that in such (uncommon) cases, there may still be a spurious Sherpa process running in the background. When Iris is forced to quit, the user needs to check if a Sherpa process is still running, and manually end it, before restarting Iris.

o If the SAMP hub (which allows Specview and Sherpa to communicate) is shut down, neither Specview nor Sherpa can automatically start a new one. The user must start a new hub manually to restore communication between Specview and Sherpa.

o No facility for handling and displaying bad data points exist yet.

o No user interaction with the multi-segment SED data structure exists yet.

o In the SedImporter, the user can broadcast a SED to Iris. But if Iris is not already running, then the SED is not broadcast to any application. Right now, the user is not warned about this failure to send the SED; a warning message should be added for this case.

o If SedImporter starts a SAMP hub, SedImporter will shut down that hub upon exit. If Iris is still running when that happens, then Iris will not be able to perform fits or calculate confidence limits, because Specview and Sherpa can communicate only if a SAMP hub is running. (Specview and Sherpa do not automatically start a new hub in this scenario.) To restore the ability to perform fits in Iris, the user will need to manually start a new SAMP hub (e.g., by re-starting the SedImporter)

o For compliance with Iris, unit strings are not saved in the IVOA compliant format.

The names of the quantities written to SedImporter output setup files have changed in the current version, therefore older setup files cannot be used for SED building in release 1.0.