#
AIPS HELP file for UVBXFN in 31DEC20

#### As of Tue Jul 7 4:15:29 2020

### HELP SECTION

UVBXFN
Type: Adverb (Real)
Use: The type of function used when counting for uniform
weighting. If UVBOX = 0, this is irrelevant since all
functions are 1 at the center cell. If UVBXFN < 0, the
function is taken as a function in U and V [i.e. the
counting weight = f(du)*f(dv)]; if UVBXFN > 0, the function
is taken as a function in radius [i.e. the counting weight
= f(sqrt(du*du+dv*dv))] giving everything approxiamtely
circular support.
If ABS(UVBXFN) = K, then
K = 1 : Pill box f(x) = 1 (x <= UVBOX)
K = 2 : linear f(x) = 1 - x / (UVBOX+1)
K = 3 : exponential f(x) = exp(-2x/(UVBOX+1))
K = 4 : Gaussian f(x) = exp(-(2x/(UVBOX+1))**2)
Other details: f(x) >= 0 and f(x) = 0 when x > UVBOX.
du and dv take only integer values: 0, 1, 2, ... UVBOX.
Null value: 0 => 1, < -4 => -1, > 4 => 1
Tasks:
IMAGR.....Fourier transform and Clean UV data with a full
range of calibration, weighting, Cleaning, and
wide-field correction options.

### EXPLAIN SECTION