[daip] problems for IMAGR in current AIPS

[Eric Greisen]

Hau Yu Liu wrote:
> Dear Dr. Greisen,
> 
>   I'm currently a visitor in AOC, and is using the computer 'HAMAL' in room 209
> to reduce the VLA data. The basic calibrations can be done smoothly. However,
> the task 'IMAGR' is terminated unexpectedly with some warning (pasted below). 
> I fetch the same uv data to my laptop can do 'IMAGR' again using the 31DEC08 
> version AIPS, then I can do imaging without any problem. 
> Do I need to do anything special in the new version of aips before doing imaging?
> 
> 
> 
> MSGserver: Starting AIPS task logging, Unix (local) domain
> 
> hostna> task #: Message
> ----------------------------------------
> 
> HAMAL > IMAGR1: Task IMAGR  (release of 31DEC09) begins
> HAMAL > IMAGR1: Doing no flagging this time
> HAMAL > IMAGR1: Create AS724_G106  .IMAGR .   1 (UV)  on disk  2  cno    1
> HAMAL > IMAGR1: Beginning channel    1 through    1 with  1 IFs
> HAMAL > IMAGR1: IMACPY: Only   439770 samples of   493427 fell on UV grid
> HAMAL > IMAGR1: **** WARNING data discarded outside usable part of UV plane ***
> HAMAL > IMAGR1: **** Actual Umax 2.9034E+06 exceeds limit 1.4213E+06        ***
> HAMAL > IMAGR1: **** Use cellsize <   0.02448 not   0.05000 to get all data ***
> HAMAL > IMAGR1: **** using a U guard band of  0.300 of a radius             ***
> HAMAL > IMAGR1: **** Actual Vmax 1.9206E+06 exceeds limit 1.4213E+06        ***
> HAMAL > IMAGR1: **** Use cellsize <   0.03700 not   0.05000 to get all data ***
> HAMAL > IMAGR1: **** using a V guard band of  0.300 of a radius             ***
> HAMAL > IMAGR1: **** WARNING data included out of inner portion of UV plane ***
> HAMAL > IMAGR1: **** Watch for high-frequency & other poor cleaning effects ***
> HAMAL > IMAGR1: QINIT: did a GET  of      5120 Kwords, OFF        -83900085
> HAMAL > IMAGR1: GRDFLT: X and Y convolution type = SPHEROIDAL
> HAMAL > IMAGR1: GRDFLT: X and Y parms =  3.0000  1.0000
> HAMAL > IMAGR1: GRDFLT: convolution function sampled every 1/100 of a cell
> HAMAL > IMAGR1: GRDMEM: Frequency 2.382213E+10 Hz
> HAMAL > IMAGR1: Field    1 Sum of gridding weights =  1.09091E+09
> HAMAL > IMAGR1: Field    1 Beam min =  -43.9 MilliJy, max =    1.0      Jy
> HAMAL > IMAGR1: Fit Gaussian FWHM =  162.047 x  111.572 Milliarcsec, PA=   17.9
> HAMAL > IMAGR1: CLBHIS: minimum component 0.167 of current peak
> HAMAL > IMAGR1: Field    1 min =  -17.5 MilliJy,max =   67.5 MilliJy
> HAMAL > IMAGR1: Loading field    1 from -1.75E-02 to  6.75E-02 interp by 7
> HAMAL > IMAGR1: You have   600 seconds to select a menu item by:
> HAMAL > IMAGR1: Press buttons A, B, or C to choose an operation
> HAMAL > IMAGR1: Press button D for on-line help
> HAMAL > IMAGR1: Clean continuing
> HAMAL > IMAGR1: BGC Clean: using  251 cell beam + residuals >     1.37 MilliJy
> HAMAL > IMAGR1: OBJECT NAMED                                  IS NOT DEFINED
> HAMAL > IMAGR1: CLBSHV: ERROR LOADING BEAM FOR
> HAMAL > IMAGR1: CLNCYC: ERROR CLEANING CLEAN process object
> HAMAL > IMAGR1: CLNUV1 : ERROR CLEANING CLEAN process object
> HAMAL > IMAGR1: CLNUV : ERROR CLEANING CLEAN process object
> HAMAL > IMAGR1: Deleting UV work file:
> HAMAL > LOGFILE FOR USER 2692 GETTING LARGE: USE PRTMSG AND CLRMSG NOW!        
> HAMAL > IMAGR1: Destroyed  1 extension files of type AN
> HAMAL > IMAGR1: Destroyed  1 extension files of type FQ
> HAMAL > IMAGR1: Destroyed UV image file: catno=      1 disk= 2
> HAMAL > IMAGR1: Purports to die of UNNATURAL causes
> HAMAL > IMAGR1: hamal 31DEC09 TST: Cpu=      2.0  Real=      6  IO=        66
> 

The error has been found.  Use OVERLAP=2 to avoid it.  The bug will be 
corrected but probably not until after 10 pm tonight.

Eric Greisen