HP4 = split a regular heptagon in 4 equal area pieces with minimum perimeter
     origin of coordinates:  in the middle of the pentagon
     if there are symmetries in the solution the data are given only for the significant part
     radius of circumscribed circle = 1

border
     (           0,	-1)
     ( 0.781831482,	-0.623489802)
     ( 0.974927912,	0.222520934)
     ( 0.433883739,	0.900968868)
     (-0.433883739,	0.900968868)
     (-0.974927912,	0.222520934)
     (-0.781831482,	-0.623489802)
     (           0,	-1)

vertex 1    ( 0.120844089,	 0.088802936)
     arc 11 (-38.72210099,	-19.64758103) 43.56947595 [centercoordinates and radius]
     arc 12 ( 2.118862604,	-1.211927799) 2.384109568 [centercoordinates and radius]
     arc 13 (           0,	-2.168385282) 2.260420746 [centercoordinates and radius]

yields the following cutlength
     CL* = 3.627309588

in units of sidelenght: 
     CL=CL*/(2*0.433883739)=4.180047858