WHATSNEW in 31DEC99 AIPS

AIPS for the Ages

last edited 29 January 2000

Imaging:

1. IMAGR
   • The output names of all imaging tasks were changed to be decimal rather than extended hex and to be 1-based rather than 0 relative. The are now xCLnnn, xIMnnn, xBMnnn where x is the Stokes and nnn = 001-512. Both the new and the old names are supported by all CC model using tasks (e.g. CALIB, UVSUB, ...)
   • Added option ALLOKAY to allow IMAGR to restart without recomputing beam images and without recomputing residual data, if the user says that all is okay.
   • Added the ability to image and Clean with both point and Gaussian component models. "Simultaneous" Cleans with multiple resolutions may help with the corrugation and extended source problems traditional in Hogbom Cleans.
   • A bug affecting multi-field gridding when the first field was done in memory but later fields required disk-based gridding was corrected.
   • A bug affecting FILEBOX operations on boxes outside the current filed of view was corrected.
   • A bug causing IMAGR to use the wrong scratch files for the gridded subtraction was corrected. This would appear as an attempt to read beyond the end of file when the beam is the same size as the image. Otherwise, it was probably negligable.
   • The maximum number of Clean boxes per field was changed so that up to 2048 may be used so long as the number of fields is <= 64. The maximum number decreases to 256 for 512 fields.
2. SCIMG - a new task which is a multi-field version of SCMAP to do iterative self-cal and imaging.
3. MAPPR is a new procedure which simplifies the inputs to IMAGR for imaging a single field without calibration, wide-field options, multiple resolutions, and the SDI method.

   Visibility data:

4. EDITR, EDITA, SNEDT :
   • The new CROWDED adverb controls whether multiple IFs and/or polarizations may appear on the plots and be edited at the same time.
   • They now accept the REASON adverb for an initial value.
   • They use certain fixed plot scales and mode settings when starting in expert mode.
   • They support scaling amplitude from 0 to max.
   • They do a new TV option to display/edit the NEXT CORRELATOR.
   • To save time, difference data are computed only when needed.
   • The ANTUSE adverb is used to select which data are displayed initially.
5. SPFLG has a changed and more general meaning to the SWITCH ALL-BL FLAG control.
6. UVCOP did not do the proper time correction when copying a single subarray from a multi-array data set. It subtracted 5 days too many.
7. CALIB, FRING, KRING had problems re-referencing the phases when delays and rates are present.
8. SPLAT was changed to make a single-source output file properly when only one source is selected.
9. CONFI has new options to control/limit the configurations being optimized.
10. FRING and KRING now allow the data modeling routines to use gridded model division under user direction (CMETHOD).

    Display:

11. Tick marks are now plotted enough so that some measure of the scale is always visible.
12. VPLOT can now plot various types of data while time averaging.
13. FGPLT is a new task to display what baselines are flagged as a function of time. Try it.

    General:

14. New adverbs BPRINT, EPRINT, NPRINT, NPLOTS replaced over-used adverbs BCOUNT, ECOUNT, NCOUNT et al. in a number of tasks.
15. TBIN had problems with flagged table rows corrected.
16. Single dish tasks: BSTST has an added Clean option, BSCLN is a new beam-switched deconvolution task, BSMOD no longer requires input BS data. OTFBS now writes a TY table.
17. All CookBook chapters are being updated. Appendix Z and the Table of Contents and Index are not yet done.The latest version of each chapter can be accessed through an html version of the Table of Contents which also contains information about the revision history of each chapter.