from Numeric import *
from numarray.linear_algebra import *



class circle_solve:
    def __init__(self,x1,y1,x2,y2,x3,y3):
        self.x1=x1
        self.y1=y1
        self.x2=x2
        self.y2=y2
        self.x3=x3
        self.y3=y3

    def print_points(self):
        print "For points X1= %0.4f Y1= %0.4f, X2= %0.4f Y2=%0.4f, X3= %0.4f Y3 %0.4f "  % (self.x1, self.y1, self.x2, self.y2, self.x3, self.y3)
        #print self.x1, self.y1, self.x2, self.y2 ,self.x3, self.y3

    def solve_it(self):
        M11_array = array(((self.x1,self.y1,1),(self.x2,self.y2,1),(self.x3,self.y3,1)))
        M11 = determinant(M11_array)

        M12_array=array((((self.x1*self.x1)+(self.y1*self.y1),self.y1,1),((self.x2*self.x2)+(self.y2*self.y2),self.y2,1),((self.x3*self.x3)+(self.y3*self.y3),self.y3,1)))
        M12 = determinant(M12_array)

        M13_array=array((((self.x1*self.x1)+(self.y1*self.y1),self.x1,1),((self.x2*self.x2)+(self.y2*self.y2),self.x2,1),((self.x3*self.x3)+(self.y3*self.y3),self.x3,1)))
        M13 = determinant(M13_array)

        M14_array=array((((self.x1*self.x1)+(self.y1*self.y1),self.x1,self.y1),((self.x2*self.x2)+(self.y2*self.y2),self.x2,self.y2),((self.x3*self.x3)+(self.y3*self.y3),self.x3,self.y3)))
        M14 = determinant(M14_array)

        x_center = .5 * (M12/M11 )
        y_center = -.5 * (M13/M11 )
        radius  = (( x_center **2) + (y_center **2) + (M14/M11))**.5
        print "Arc center =  %0.8f,  %0.8f, with radius R %0.8f" % (x_center, y_center, radius)




# how to use this class:
one = circle_solve(0,.18,.25,0,.37,.012)
two = circle_solve(0,.18,-.0493,.3235,-0.0521,0.6357)

one.print_points()
one.solve_it()
two.print_points()
two.solve_it()