[daip] SD from ALMA

[Eric Greisen]

Ed Fomalont wrote:
> Hi Eric, Harvey and Jeff,
> 
> I have some ALMA single dish data from an OTF observation that has been 
> process by the casa single dish system.  The image that is made is not 
> so bad, but I think the gridding techniques from the calibrated OTF 
> scans to an image are not very good.  So, I wanted to put the calibrated 
> SD data into AIPS and try out the imaging with SDGRD.
> 
> The CASA single dish package did write an sdfits data set.  However, I 
> tried reading it into aips using fitld and it bombed with
> 
> LOCALH> FITLD1: Task FITLD  (release of 31DEC12) begins
> LOCALH> FITLD1: ZFI2: DELAY 1
> LOCALH> FITLD1: ZFI2: DELAY 2
> LOCALH> FITLD1: ZFI2: REQUEST FOR BYTES 5121 THRU = 6144
> LOCALH> FITLD1: ZFIO: OPER = READ LUN = 15 NREC =        6
> LOCALH> FITLD1: ZFI2: BEYOND EOF = 5120
> LOCALH> FITLD1: ZERROR: IN ZFI2   ERRNO = 22 (Invalid argument)
> LOCALH> FITLD1: CATDIR: I/O ERROR READING CATALOG FILES:    3
> LOCALH> FITLD1: SCREAT: ERROR    3 SEARCHING CATALOG TO MAKE SCRATCH
> LOCALH> FITLD1: ERROR   1 OPENING HISTORY SCRATCH FILE
> LOCALH> FITLD1: ERROR      1 RETURNED FROM BTFHIS
> LOCALH> FITLD1: Purports to die of UNNATURAL causes
> LOCALH> FITLD1: localhost    31DEC12 TST: Cpu=       0.0  Real=       2
> 
> 
> The 'sdfits' file is in
> 
> polaris.cv.nrao.edu:/home/ftp/NRAO-staff/efomalon/ALMA_SD
>   filename = PM02_cal.txt
> 
> Any hope of getting this into aips with minimal effort.
> 
> You can also make an askii dump of the data.
> 
> Thanks, Ed
> 

The fits file contains 1 table of a type unknown to aips - mainly 
because it uses a concept called the "heap".  A heap is a collection of 
data added to the back end of a table and pointed to by pointers in the
columns of the table.  I forget what the format code 1PE(256) is even 
supposed to mean and aips has no way to read such data.  It could be 
created but I wonder if it is a good idea to encouraged this usage which 
is probably not supported many places.

Should I work on it?  For the GBT Langston has developed software to 
take the data from the reduction package (CASA??) into aips - you might 
want to e-mail him.

Eric Greisen