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X₁₄₇₉¶

{X₁,X₄}-HARMONIC CONJUGATE OF X₁₄₇₈

X₁₄₇₉ is the {X₁,X₄}-harmonic conjugate of X₁₄₇₈.

X₁₄₇₉ ({X₁,X₄}-HARMONIC CONJUGATE OF X₁₄₇₈) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_1479 = {X_1,X_4}-HARMONIC CONJUGATE OF X_1478."""

        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,
            centroid_of,
            ceva_conjugate,
            circumcenter_of,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            feuerbach_point_of,
            incenter_of,
            orthocenter_of,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_01479(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_1479 = {X_1,X_4}-HARMONIC CONJUGATE OF X_1478 on reference triangle ABC."""
            X_1067 = eval_trilinear_point(model, A, B, C, '(1/(1 - cos(A)*(cos(B) + cos(C))))', ID="X_1067", classes=["center"])
            X_1 = incenter_of(model, A, B, C, ID="X_1", classes=["center"])
            X_1479 = ceva_conjugate(model, A, B, C, X_1067, X_1, ID="X_1479", classes=["selected", "target"])
            X_4 = orthocenter_of(model, A, B, C, ID="X_4", classes=["center", "incident"])
            central_line(model, X_1, X_4, 1, 4, incident=True)
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center", "incident"])
            X_11 = feuerbach_point_of(model, A, B, C, ID="X_11", classes=["center", "incident"])
            central_line(model, X_3, X_11, 3, 11, incident=True)
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center", "incident"])
            X_35 = eval_trilinear_point(model, A, B, C, '1 + 2*cos(A)', ID="X_35", classes=["center", "incident"])
            central_line(model, X_2, X_35, 2, 35, incident=True)
            return promote_point_to_top(model, X_1479)


        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_1479 on the given reference triangle."""
            model = create_model('X_1479 = {X_1,X_4}-HARMONIC CONJUGATE OF X_1478')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_01479(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-01479.json"))
            write_center_svg(
                model_acute,
                here / "x-01479.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X1479¶

X₁₄₇₉¶