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X₁₅₂₁¶

ORTHOJOIN OF X₁₁

X₁₅₂₁ (ORTHOJOIN OF X₁₁) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_1521 = ORTHOJOIN OF X_11."""

        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_01521(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_1521 = ORTHOJOIN OF X_11 on reference triangle ABC."""
            X_117 = point_from_barycentrics(model, A, B, C, 0.19223485, -0.017045455, 0.82481061, ID="X_117", classes=["center"])
            X_515 = eval_trilinear_point(model, A, B, C, '(b + c)*sec(A) - b*sec(B) - c*sec(C)', ID="X_515", classes=["center"])
            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"])
            central_line(model, X_117, X_515, 117, 515)
            central_line(model, X_118, X_516, 118, 516)
            X_1521 = intersect_lines(model, X_117, X_515, X_118, X_516, ID="X_1521", classes=["selected", "target"])
            return promote_point_to_top(model, X_1521)


        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_1521 on the given reference triangle."""
            model = create_model('X_1521 = ORTHOJOIN OF X_11')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_01521(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-01521.json"))
            write_center_svg(
                model_acute,
                here / "x-01521.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X1521¶

X₁₅₂₁¶