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X₁₉₂₆¶

CROSSDIFFERENCE OF PU(13)

X₁₉₂₆ (CROSSDIFFERENCE OF PU(13)) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_1926 = CROSSDIFFERENCE OF PU(13)."""

        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_trilinear_point,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_01926(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_1926 = CROSSDIFFERENCE OF PU(13) on reference triangle ABC."""
            X_1926 = eval_trilinear_point(model, A, B, C, '(1 - b**(2)*c**(2)/a**(4))', ID="X_1926", classes=["selected", "target"])
            X_38 = eval_trilinear_point(model, A, B, C, 'b**(2) + c**(2)', ID="X_38", classes=["center", "incident"])
            X_75 = eval_trilinear_point(model, A, B, C, '1/a**(2)', ID="X_75", classes=["center", "incident"])
            central_line(model, X_38, X_75, 38, 75, incident=True)
            X_76 = eval_trilinear_point(model, A, B, C, '1/a**(3)', ID="X_76", classes=["center", "incident"])
            X_257 = eval_trilinear_point(model, A, B, C, '1/(a**(3) + a*b*c)', ID="X_257", classes=["center", "incident"])
            central_line(model, X_76, X_257, 76, 257, incident=True)
            X_661 = eval_trilinear_point(model, A, B, C, 'cot(B) - cot(C)', ID="X_661", classes=["center", "incident"])
            X_786 = eval_trilinear_point(model, A, B, C, '(a **(-4)*(b **(-1) - c **(-1)) + a **(-2)*(b **(-3) - c **(-3)))', ID="X_786", classes=["center", "incident"])
            central_line(model, X_661, X_786, 661, 786, incident=True)
            return promote_point_to_top(model, X_1926)


        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_1926 on the given reference triangle."""
            model = create_model('X_1926 = CROSSDIFFERENCE OF PU(13)')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_01926(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-01926.json"))
            write_center_svg(
                model_acute,
                here / "x-01926.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X1926¶

X₁₉₂₆¶