[daip] Re:

[Eric Greisen]

Maarten van Hoven writes:

Please send aips quieries to daip at nrao.edu in future.  This is covered
when I am away.

 > I'm a student in Astronomy from Leiden University in the Netherlands. This
 > summer I will be visiting the VLA, and work on some data under supervision
 > of Dr Chris Carilli. Dr Carilli sent me a magnetic tape (DDS4) containing
 > about 5 Gbytes of GMRT data, but I encounter some difficulties in the
 > reading process. I was hoping you could help me with this.
 > I tried to read the tape using the usual Aips tasks (i.e. PRTTP, FITLD,
 > UVLOD), finding the same error all the time:
 > 
 > PRTTP1: Task PRTTP  (release of 31DEC05) begins
 > PRTTP1: ZTPWAT: ERROR   6 FOR LUN = 128 IBUFF = 2 TO TAPE
 > PRTTP1: ZERROR: IN ZTPWA2 ERRNO = 5 (Input/output error)
 > PRTTP1: ZERROR: IN ZTPWA2 ERRNO = 5 (Input/output error)

    The tape device is encountering a hard error.  The end-of-tape
suggestion is just a guess and is probably not right.

 > PRTTP1: This usually means you're at END-OF-TAPE
 > PRTTP1: TAPIO: ERROR   6  READING FILE
 > PRTTP1: ERROR      6 TRYING TO READ RECORD 2007  OF FITS DATA
 > PRTTP1: This file: read     5.521 Megabytes in    2010 logical records
 > PRTTP1: Read at least      5.521 Megabytes in    2010 logical records
 > PRTTP1: Purports to die of UNNATURAL causes
 > PRTTP1: ijssel       31DEC05 TST: Cpu=       0.0  Real=      76
 > 
 > Anything familiar?
 > 
 > PRTTP only works with adverb PRTLEV = -4 (returns table of files, skips
 > tape read). I get:

    This says that advf does skip over the tape error and that the
headers of each FITS file are readable.  Are you able to read the data
from files other than the first?

 > 
 > PRTTP1: Task PRTTP  (release of 31DEC05) begins
 > PRTTP1: WARNING: OUTPRINT='PRTTPout.txt' USED - BLANK NOT ALLOWED
 > PRTTP1: ZTXOP2: using translated file name =
 > PRTTP1: ZTXOP2: PRTTPout.txt
 > PRTTP1: Begin reading file     1
 > PRTTP1: This file: read   236.983 Megabytes in   86283 logical records
 > PRTTP1: Begin reading file     2
 > PRTTP1: This file: read  1814.373 Megabytes in  660593 logical records
 > PRTTP1: Begin reading file     3
 > PRTTP1: This file: read   269.149 Megabytes in   97994 logical records
 > PRTTP1: Begin reading file     4
 > PRTTP1: This file: read  1881.332 Megabytes in  684972 logical records
 > PRTTP1: Begin reading file     5
 > PRTTP1: This file: read   238.288 Megabytes in   86758 logical records
 > PRTTP1: Begin reading file     6
 > PRTTP1: This file: read   817.696 Megabytes in  297714 logical records
 > PRTTP1: Read at least   5257.820 Megabytes in 1914314 logical records
 > PRTTP1: Appears to have ended successfully
 > PRTTP1: ijssel       31DEC05 TST: Cpu=       0.0  Real=     132
 > 
 > Alternative ways of reading don't work either; tar, dd
 > I'd really appreciate any suggestions on wat to do.

If dd does not work then there is really simply something wrong with
the tape.

Eric Greisen