Fig165bis.tex

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        /R 4 def
        /T 1 def
        /a 6.28 R mul def
        /X a t mul T div def
        /Angle \rTheta\space 360 t mul T div add def
        Angle 89 gt {/Angle 89 def} if
        Angle -89 lt {/Angle -89 def} if
        /Y X Angle dup sin exch cos div mul def
        X Y}
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