GC-06.03 · Symbolic Model & Source

Companion symbolic Python construction for GC-06.03 · Bùi Quang Tuân’s Four Congruent Golden Circles (GC-06.03).

Programmatic Usage

from geometor.divine.catalog import build_construction

        model, cert = build_construction("GC-06.03")
        assert cert.ratio_expr == sp.GoldenRatio
        

Exact Builder Implementation

def build_bui_four_golden_circles() -> ConstructionResult:
            """Bùi Quang Tuân's four congruent circles generating a vertical golden chain."""
            m = new_catalog_model("bui-four-golden-circles")
            s3 = sp.sqrt(3)
            s15 = sp.sqrt(15)

            A = m.set_point(-sp.Rational(1, 2), 0, classes=["given"], ID="A")
            B = m.set_point(sp.Rational(1, 2), 0, classes=["given"], ID="B")
            c_a = m.construct_circle(A, B, classes=["primary"], ID="cA")
            c_b = m.construct_circle(B, A, classes=["primary"], ID="cB")

            E = m.intersect(c_a, c_b, side_of=(A, B, 1), classes=["golden"], ID="E")
            N = m.intersect(c_a, c_b, side_of=(A, B, -1), classes=["golden"], ID="N")
            ln_axis = m.construct_line(N, E, classes=["golden"], ID="NE")
            _ = ln_axis

            # Congruent unit circles centered at D=(0, sqrt(15)/2) and C=(0, -sqrt(15)/2) tangent to cA, cB
            D = m.set_point(0, s15 / 2, classes=["golden"], ID="D")
            C = m.set_point(0, -s15 / 2, classes=["golden"], ID="C")
            T1 = m.set_point(-sp.Rational(1, 4), s15 / 4, guide=True, ID="T1")
            T2 = m.set_point(-sp.Rational(1, 4), -s15 / 4, guide=True, ID="T2")
            m.construct_circle(D, T1, classes=["golden"], ID="cD")
            m.construct_circle(C, T2, classes=["compass"], ID="cC")
            _ = s3

            return make_result(m, ("E", "N"), ("E", "D"), ("N", "E", "D"))
        

Exact Symbolic Point Coordinates

All points in bui-four-golden-circles are certified free of floating-point approximations over \(\mathbb{Q}(\sqrt{3}, \phi)\):

Point

Exact \(x\)

Exact \(y\)

A

\(- \frac{1}{2}\)

\(0\)

B

\(\frac{1}{2}\)

\(0\)

E

\(0\)

\(\frac{\sqrt{3}}{2}\)

N

\(0\)

\(- \frac{\sqrt{3}}{2}\)

D

\(0\)

\(\frac{\sqrt{15}}{2}\)

C

\(0\)

\(- \frac{\sqrt{15}}{2}\)

Certified Golden Ratio: EN / ED = GoldenRatio.