Sanity tests

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Sanity Checks

Here we will quickly go over some commands to test basic functionality of miriad: getting the data into miriad and displaying this data using pgplot routines. We also suggest to install ds9 and the associated XPA tools. Although mostly for images and cubes, it can also be used to browse your visbility data bricks. An additional, image cube visualization package we recommend for Miriad is karma

Image Data and Display

Generating an image and displaying it in miriad:

 % imgen out=map0
 % hexdump -C map0/header | tail
 000001c0  6e 61 78 69 73 00 00 00  00 00 00 00 00 00 00 08  |naxis...........|
 000001d0  00 00 00 02 00 00 00 02                           |........|

The important thing to note is the last line, if endianism is wrong on your machine, the last 4 bytes might read as 2,0,0,0 instead of 0,0,0,2. As in FITS files, data in miriad are stored in a big-endian fashion, which means on intel chips (little-endian) data will need to be byte swapped.

Now display the data

 % implot in=map0 device=/xs
 % ds9 &
 % mirds9 map0

And to make sure your random number generator works:

 % imgen out=map1 object=noise spar=1
 % histo in=map1 | grep Rms
 Mean -3.29890E-04 Rms  9.99046E-01 Flux -2.16197E+01 Jy (65536 points)

Visibility Data and Display

Getting a Carma visibility dataset from the archive and displaying some basic properties of the data

 % wget -O - | tar zxf -
 % curl | tar zxf -
 % itemize in=flux.rpnt.2007may31.9.miriad
 Itemize: Version 22-jun-02
   obstype  = mixed-auto-cross
   nwcorr   = 12600
   ncorr    = 189000
   vislen   = 1048928
   wflags     (integer data, 407 elements)
   flags      (integer data, 6097 elements)
   visdata    (binary data, 1048924 elements)
   history    (unknown data, 0 elements)
   vartable   (text data, 650 elements)

 % uvplt vis=flux.rpnt.2007may31.9.miriad device=/xs

WIP: a pgplot based plotting package

Give the following commands to see if you have your environment setup correctly:

 % wip -d /xs
 WIP> box
 WIP> end
 % wip -d /gif
 WIP> box
 WIP> end
 % wip -d /ps
 WIP> box
 WIP> hardcopy
 WIP> end
 % wip -d /xd
 WIP> image map0
 WIP> header rd rd
 WIP> halftone
 WIP> end

Be careful with that last example, the hardcopy command would spool your file to your default printer,unless you have modified your .wipinit file with something like

 set "print" echo Printfile in %s

or simply

 set print ignore

A final byteswapping test in from a miriad image:

 % wip -d /xd
 WIP> image map0
 WIP> header rd rd
 WIP> halftone
 WIP> end

should show just a blob in the center.

Software Development

  • Assuming your Miriad is CVS enabled (i.e. you will see the $MIR/CVS directory), you should test if you can update Miriad using cvs:
  % cd $MIR
  % cvs -nq update

If this failed with a command not found, cvs should be installed. Another failure mode is not having a ~/.cvspass entry for the anonymous access to the UMD cvs server. For this do:

  % cvs login
  % cvs -nq update
  • Testing to see if you can compile a subroutine or program, try these:
  % mirboss
  % mir.subs fitsio
  % mir.prog itemize
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