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X₃₅₇₉¶

INTERSECTION OF LINES X₁X_3 AND X₁₀X_30

X₃₅₇₉ (INTERSECTION OF LINES X₁X_3 AND X₁₀X_30) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_3579 = INTERSECTION OF LINES X_1X_3 AND X_10X_30."""

        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,
            ceva_conjugate,
            circumcenter_of,
            construct_baseline_triangle,
            create_model,
            eval_barycentric_point,
            eval_trilinear_point,
            incenter_of,
            promote_point_to_top,
            spieker_center_of,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_03579(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_3579 = INTERSECTION OF LINES X_1X_3 AND X_10X_30 on reference triangle ABC."""
            X_3210 = eval_barycentric_point(model, A, B, C, '(a**(2)*(b + c) + a*(b**(2) - b*c + c**(2)) - b*c*(b + c))', ID="X_3210", classes=["center"])
            X_37 = eval_trilinear_point(model, A, B, C, 'b + c', ID="X_37", classes=["center"])
            X_3579 = ceva_conjugate(model, A, B, C, X_3210, X_37, ID="X_3579", classes=["selected", "target"])
            X_1 = incenter_of(model, A, B, C, ID="X_1", classes=["center", "incident"])
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center", "incident"])
            central_line(model, X_1, X_3, 1, 3, incident=True)
            X_10 = spieker_center_of(model, A, B, C, ID="X_10", classes=["center", "incident"])
            X_30 = eval_trilinear_point(model, A, B, C, 'cos(A) - 2*cos(B)*cos(C)', ID="X_30", classes=["center", "incident"])
            central_line(model, X_10, X_30, 10, 30, incident=True)
            X_72 = eval_trilinear_point(model, A, B, C, '(b + c)*cot(A)', ID="X_72", classes=["center", "incident"])
            X_74 = eval_trilinear_point(model, A, B, C, '1/(cos(A) - 2*cos(B)*cos(C))', ID="X_74", classes=["center", "incident"])
            central_line(model, X_72, X_74, 72, 74, incident=True)
            return promote_point_to_top(model, X_3579)


        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_3579 on the given reference triangle."""
            model = create_model('X_3579 = INTERSECTION OF LINES X_1X_3 AND X_10X_30')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_03579(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-03579.json"))
            write_center_svg(
                model_acute,
                here / "x-03579.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X3579¶

X₃₅₇₉¶