; ROTMEAS
;---------------------------------------------------------------
;! Tells the rotation measure of a source
;# ADVERB CALIBRATION POLARIZATION
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
ROTMEAS   LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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ROTMEAS
Type: Adverb  (real)
Use:  Used to tell a task a rotation measure in radians per meter
      squared.

Null value:  0 -> no rotation measure

Tasks:
   SPLIT....Converts multi-source to single-source UV files with
            calibration.  It ROTMEAS is not zero, the output is forced
            to IQUV or RR/LL/RL/LR Stokes and Q and U are corrected by
            the rotation measure into the values they would have at 0
            wavelength.
                Qout = Uin sin(2D) + Qin cos(2D)
                Uout = Uin cos(2D) - Qin sin(2D)
                RLout = RLin (cos(2D) - j sin(2D))
                LRout = LRin (cos(2D) + j sin(2D))
            where j = sqrt(-1) and D = ROTMEAS * Lambda^2.
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