; UVWAX ;--------------------------------------------------------------- ;! flags uv samples near the U,V axes to reduce interference ;# TASK UV UTILITY ;----------------------------------------------------------------------- ;; Copyright (C) 2001-2002 ;; Associated Universities, Inc. Washington DC, USA. ;; ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2 of ;; the License, or (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public ;; License along with this program; if not, write to the Free ;; Software Foundation, Inc., 675 Massachusetts Ave, Cambridge, ;; MA 02139, USA. ;; ;; Correspondence concerning AIPS should be addressed as follows: ;; Internet email: aipsmail@nrao.edu. ;; Postal address: AIPS Project Office ;; National Radio Astronomy Observatory ;; 520 Edgemont Road ;; Charlottesville, VA 22903-2475 USA ;----------------------------------------------------------------------- UVWAX LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC UVWAX Task which flags points close to the U = 0 and/or V=0 INNAME Input UV file name (name) INCLASS Input UV file name (class) INSEQ 0.0 9999.0 Input UV file name (seq. #) INDISK 0.0 9.0 Input UV file disk unit # OUTNAME Output UV file name (name) OUTCLASS Output UV file name (class) OUTSEQ -1.0 9999.0 Output UV file name (seq. #) OUTDISK 0.0 9.0 Output UV file disk unit #. APARM (1) Min U distance flagged (2) Max U distance flagged (3) Min V distance flagged (4) Max V distance flagged (5) Min W distance flagged (6) Max W distance flagged (wavelengths) ---------------------------------------------------------------- UVWAX Task: This task flags UV data which is between APARM(1) and APARM(2) wavelengths from the U axis and also between APARM(3) and APARM(4) wavelengths from the V axis. It will also flag data between APARM(5) and APARM(6) wavelengths from the W axis. The fringe rate is 0 on the V axis (u = 0), so the rejection by averaging of unwanted terrestrial signals due to interference and other bad data, fails near U = 0. In addition to axis flagging, It can also be used to remove any axisymmetric part of the UV plane which is undesirable for some other reason. Flagging large W-values can be useful when the 3-D imaging problem gets too big for AIPS to handle with fewer then 512 facets (ie by removing large W, you can make fewer, bigger facets). This is a heavily modified version of UVNOU; contact Wendy Lane for advice. Adverbs: INNAME.....Input UV file name (name). Standard defaults. INCLASS....Input UV file name (class). Standard defaults. INSEQ......Input UV file name (seq. #). 0 => highest. INDISK.....Disk drive # of input UV file. 0 => any. OUTNAME....Output UV file name (name). Standard defaults. OUTCLASS...Output UV file name (class). Standard defaults. OUTSEQ.....Output UV file name (seq. #). 0 => highest unique OUTDISK....Disk drive # of output UV file. 0 => highest with space for the file. APARM......(1) Smallest abs(U) distance flagged (wavelengths) [ <=0 => defaults to 0 wavelengths] (2) Largest abs(U) distance flagged (wavelengths) [ =0 => defaults to 10^30 wavelengths] (3) Smallest abs(V) distance flagged (wavelengths) [ <= 0 => defaults to 0 wavelengths] (4) Largest abs(V) distance flagged (wavelengths) [ = 0 => defaults to 10^30 wavelengths] i.e., all data with abs(U) betweem APARM(1) and APARM(2) AND abs(V) between APARM(3) and APARM(4) will be flagged. Defaults are to flag U/V values between 0 and (effectively) infinity. Optionally you can also flag W: (5) Smallest abs(W) distance flagged (wavelengths) [ <= 0 => defaults to 10^30 wavelengths] (6) Largest abs(W) distance flagged (wavelengths) [ = 0 => defaults to 10^30 wavelengths] Note: U, V, W are evaluated only at the reference frequency; changes of U, V, W with spectral channel or IF are ignored. ----------------------------------------------------------------