[daip] more IMAGR problems

[Lynn D. Matthews]

I've encountered another failure with IMAGR (messages appended below). I 
had it running overnight with autoboxing and filtering turned on, plus a 
flux limit set.

It got through 161 channels successfully, none of which had detectable 
emission in them. It then choked on channel 162, the first channel with 
emission present. The emission is fairly weak, but strong enough 
that it should exceed the boxing threshold.

I did a couple of experiments. Setting FLUX=0 and turning off filtering 
had no effect. But when I turned autoboxing off, and the failure no longer 
occurs. With autoboxing on, I found that if I try to clean only one 
channel, failures occur in the earlier channels of the cube where there 
was no previous problem. Tweaking the IM2PARM parameters seemed to have no 
effect.

Lynn Matthews

wrest > IMAGR1: Beginning channel  162 through  162 with  1 IFs
wrest > IMAGR1: Doing no flagging this time
wrest > IMAGR1: UVWAIT: begin finding uniform weights
wrest > IMAGR1: UVWAIT: Average grid weight  2.064E-06
wrest > IMAGR1: UVWAIT: Adding temperance S  4.128E-07
wrest > IMAGR1: UVWAIT: begin applying uniform or other weights
wrest > IMAGR1: UVWAIT: Sum of weights in  8.206E-03 and out  1.510E-02
wrest > IMAGR1: UVWAIT: Noise is increased by a factor 1.277 due to 
weighting
wrest > IMAGR1: UVWAIT: Average summed weight  2.064E-06 over     362048 
vis
wrest > IMAGR1: GRDMEM: Frequency 4.311786E+10 Hz
wrest > IMAGR1: Field    1 Sum of gridding weights =  1.60281E-01
wrest > IMAGR1: Field    1 Beam min = -196.3 MilliJy, max =    1.0      Jy
wrest > IMAGR1: Fit Gaussian FWHM =  538.141 x  177.977 Microarcsec, PA= 
-12.5
wrest > IMAGR1: CLBHIS: minimum component 0.500 of current peak
wrest > IMAGR1: Field    1 use FWHM=  550.000 x  190.000 Microarcsec, PA= 
0.0
wrest > IMAGR1: QCLEAN: Make copy of data for filtering
wrest > IMAGR1: Field    1 min =  -67.6 MilliJy,max =   79.2 MilliJy
wrest > IMAGR1: VISDFT: Begin DFT component subtraction
wrest > IMAGR1: VISDFT: fields 1 - 1 chns 1 - 1 in 1 CC models
wrest > IMAGR1: VISDFT: Model components of type Point
wrest > IMAGR1: VISDFT: ERROR    1 NO POINT COMPONENTS FOUND
wrest > IMAGR1: OUMSUB: ERROR SUBTRACTING CLEAN field number 0001
wrest > IMAGR1: OUMSUB: FROM UVdata work object
wrest > IMAGR1: UVSUBM: ERROR SUBTRACTING CLEAN field number 0001
wrest > IMAGR1: UVSUBM: FROM UVdata work object
wrest > IMAGR1: CLNUV1 : ERROR CLEANING CLEAN process object
wrest > IMAGR1: CLNUV : ERROR CLEANING CLEAN process object
wrest > IMAGR1: Deleting UV work file:
wrest > IMAGR1: Destroyed  1 extension files of type AN
wrest > IMAGR1: Destroyed  1 extension files of type FQ
wrest > IMAGR1: Destroyed UV image file: catno=    314 disk= 3
wrest > IMAGR1: Purports to die of UNNATURAL causes
wrest > IMAGR1: wrest 31DEC09 TST: Cpu=   3620.6  Real=   4899  IO= 
319759