q = w * g,
a = n / q,
h = a ( cosh ( l / ( 2* a )) - 1),
s = 2 * a * sinh ( l / ( 2* a ))
Where,
q = cable weight per unit length,
w = cable mass per unit length,
g = force perpendicular to cable length,
a = angle between x axis and cable sector,
n = cable tension,
l = straight line distance,
h = cable sag,
s = cable length.
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Formula 
