subarray
Return the number of telescopes in a given sub-array.
EXAMPLE
-------

Example 1  -  Write a message saying how many telescopes are in the first
              sub-array.

0> print "There are", ntel, "telescopes in sub-array 1"
There are 13 telescopes in sub-array 1 

Example 2  -  List the names of all 'ntel' telescopes in sub-array 2.

0> do i=1,ntel(2)
1>   print telname(i,2)
1> end do
BONN 
WSRT 
JBNK1 
BOLOGNA 
VLBA_KP 
VLBA_PT 
VLBA_LA 
VLA27 
OVRO 
0>

PARAMETERS
----------
subarray  -  Optional: Defaults to 1.
             This is the number of the antenna sub-array to return the
             telescope count from. The 'header' command may be used to
             examine what sub-arrays are available.

RELATED FUNCTIONS
-----------------
telname  -  Return the name of the n'th telescope of a given sub-array.