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X₂₆₇₈¶

RS(X₇₄, X₁₀₁)

X₂₆₇₈ = reflection of X₂₆₈₅ in X₁₈₈

X₂₆₇₈ (RS(X₇₄, X₁₀₁)) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_2678 = RS(X_74, X_101)."""

        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,
            intersect_lines,
            point_from_barycentrics,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_02678(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_2678 = RS(X_74, X_101) on reference triangle ABC."""
            X_118 = point_from_barycentrics(model, A, B, C, 0.28918651, -0.056547619, 0.76736111, ID="X_118", classes=["center"])
            X_516 = eval_trilinear_point(model, A, B, C, 'b*c*((a - b)*cot(C) + (a - c)*cot(B))', ID="X_516", classes=["center"])
            X_125 = eval_trilinear_point(model, A, B, C, 'cos(A)*(sin(B - C))**(2)', ID="X_125", classes=["center"])
            X_523 = eval_trilinear_point(model, A, B, C, 'sin(B -C)', ID="X_523", classes=["center"])
            central_line(model, X_118, X_516, 118, 516)
            central_line(model, X_125, X_523, 125, 523)
            X_2678 = intersect_lines(model, X_118, X_516, X_125, X_523, ID="X_2678", classes=["selected", "target"])
            return promote_point_to_top(model, X_2678)


        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_2678 on the given reference triangle."""
            model = create_model('X_2678 = RS(X_74, X_101)')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_02678(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-02678.json"))
            write_center_svg(
                model_acute,
                here / "x-02678.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X2678¶

X₂₆₇₈¶