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X₃₉₇₃¶

X₃₁₆₁com(EXCENTRAL TRIANGLE)

X₃₉₇₃ (X₃₁₆₁com(EXCENTRAL TRIANGLE)) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_3973 = X_3161com(EXCENTRAL TRIANGLE)."""

        from __future__ import annotations

        from pathlib import Path

        import sympy.geometry as spg
        from geometor.model import Model

        from geometor.etc.ops import (
            central_line,
            construct_baseline_triangle,
            create_model,
            eval_barycentric_point,
            eval_trilinear_point,
            incenter_of,
            promote_point_to_top,
            symmedian_point_of,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_03973(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_3973 = X_3161com(EXCENTRAL TRIANGLE) on reference triangle ABC."""
            X_3973 = eval_barycentric_point(model, A, B, C, '(a*(3*b +3*c - 5*a))', ID="X_3973", classes=["selected", "target"])
            X_1 = incenter_of(model, A, B, C, ID="X_1", classes=["center", "incident"])
            X_6 = symmedian_point_of(model, A, B, C, ID="X_6", classes=["center", "incident"])
            central_line(model, X_1, X_6, 1, 6, incident=True)
            X_173 = eval_trilinear_point(model, A, B, C, 'cos(B/2) + cos(C/2) - cos(A/2)', ID="X_173", classes=["center", "incident"])
            X_363 = eval_trilinear_point(model, A, B, C, 'b/(1 + sin(B/2)) + c/(1 + sin(C/2)) - a/(1 + sin(A/2))', ID="X_363", classes=["center", "incident"])
            central_line(model, X_173, X_363, 173, 363, incident=True)
            X_200 = eval_trilinear_point(model, A, B, C, '(cot(A/2))**(2)', ID="X_200", classes=["center", "incident"])
            X_902 = eval_trilinear_point(model, A, B, C, 'a*(b + c - 2*a)', ID="X_902", classes=["center", "incident"])
            central_line(model, X_200, X_902, 200, 902, incident=True)
            return promote_point_to_top(model, X_3973)


        def build_model(
            sides: tuple[float, float, float] = (5.0, 6.0, 7.0),
            show_guides: bool = False,
        ) -> Model:
            """Build a `geometor.model.Model` for X_3973 on the given reference triangle."""
            model = create_model('X_3973 = X_3161com(EXCENTRAL TRIANGLE)')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_03973(model, A, B, C)
            return model


        if __name__ == "__main__":
            here = Path(__file__).resolve().parent
            model_acute = build_model((5.0, 6.0, 7.0))
            model_acute.save(str(here / "x-03973.json"))
            write_center_svg(
                model_acute,
                here / "x-03973.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X3973¶

X₃₉₇₃¶