"Map data Extraction" "me"				R. W. Wilson


me rd: 5:32:47 -05:24:30 nbe: fs: ps: smacro:"smac" rmacro:"rmac"\
	emacro "emac" sn:92a1000_2000

    Search through the given scans for scans with center position of
    Orion A, get the nbe, and call the given macros.  The stored 
    default scan number will not be changed (but it would have been set
    to 92a2000 if update had been given).

me rd: 5:32:47 -05:24:30 -45_30 -120_100 nbe: fs: ps: smacro:"smac"\
	rmacro:"rmac" emacro:"emac" update:

    Same as before, except that any scan falling in the box with ra
    offset between -45 and 30 'Arc and dec between -120 and 100 'Arc
    of the center of Orion A will be accepted independent of its
    'center position'.  The default starting scan will be used and
    me will continue until it reaches the end of the last file
    in the sequence (c92a10001 will be followed by c92b1).  The
    default starting scan number will be updated.

me lb: 0 0 30_31 -.5_.5 bbe: ps: smacro:"smac" rmacro:"rmac" emacro:"emac"

    Search the box from 30 to 31 deg in l and +/- 0.5 deg in b. Note
    idiom for searching areas in galactic coordinates: any scan with an
    ``offset'' from the origin of galactic coordinates by 30 to 31 degrees
    in l and +/- 0.5 degrees in b is accepted. The scan's center position
    doesn't have to be 0 0; it need only fall in the specified box.

DESCRIPTION: !!! NOTE: me's mode of operation was changed in 3/92 !!!

'Me' is designed to automatically look through a data file [and its
successors] and extract the data which belongs in the map in the
current stacks directory.  It is also useful for scanning a data file
for observations of a given set of types (eg. FS or PS) in a region of
the sky (or with a given center position) and at a range of
frequencies.  Additional filters may be applied in the user's
processing macro.

When 'me' finds the first scan which satisfies the given criteria, it
gets that scan, and calls the start up macro ('smacro:' in the parse
tree) to start the process.  It then re-gets that scan and calls the
data reduction macro ('rmacro:').  Subsequent scans in the map have
only 'rmacro' called.  It is the responsibility of 'rmacro' to do any
data storage which is desired, but it can assume that the scan in stack
1 fits the criteria for the map.  At the end of the range of scans or
when the file ends, the ending macro ('emacro:') is called.  At the
time 'rmacro' is called for the first scan of a given map, the next
stack number is put in global variable 1 "#1".  Thus 'emacro' can
expect to have the first stack number in #1 and the last stack where
'rmacro' left it (st a: sets .numst to the number of the stack where
stack 1 was stored).  In most cases a macro for calling me and the
processing macros will be defined in the stack macro file for the map.

The macros may be left undefined if no action is required, although
if no macros are given the only effect of running me will be to update
the record of the last scan processed if requested.

If me finishes correctly, it will store the file and number of the
last scan processed in the stacks default file.  A subsequent run
of me with no scan number will start up from that point.

If you interrupt 'me' or it otherwise fails to finish properly it will
not update the last scan processed.  I suspect that the most common
problem with 'me' will be duplicating scans in the stacks.  If you want
to play with 'me' and do no harm, replace the store command in 'rmacro'
with a print command.  I recommend keeping track of maps manually to
check up on 'me'.

See the documentation for gt for a discussion of scan numbers in comb.

This document was last updated on Tue Oct 17 16:24:05 EDT 2000 by Marc W. Pound.