如果不知道中心和半径,如何绘制经过四个点的球体?

如果不知道中心和半径,如何绘制经过四个点的球体?

基于这张纸,我有一个 Heronian 四面体,是具有顶点的格子四面体O(0, 0, 0), A(15, -60, 20), B(96, 120, 128), C(63, 84, 56),并且
基于 这个答案我试过

\documentclass[tikz,border=2 mm,12pt]{standalone}
\usepackage{fouriernc}
\usepackage{tikz-3dplot-circleofsphere}
\begin{document} 
    \tdplotsetmaincoords{75}{170} 
    \begin{tikzpicture}[scale=1/10,line cap=butt,line join=round,tdplot_main_coords,declare function={R= 5*sqrt(451369)/14;%
    }] 
    \path 
    coordinate (O) at (0, 0, 0) 
    coordinate (A) at (15, -60, 20) 
    coordinate (B) at (96, 120, 128)
    coordinate (C) at (63, 84, 56)
    coordinate (I) at   (-1383/14, 90/7, 1528/7)
    ; 
    \begin{scope}[tdplot_screen_coords]
    \draw[thick] (I) circle (R);
    \end{scope}
    \end{tikzpicture} 
\end{document}

由于尺寸太大,我无法获得结果。如果不计算球心和半径的坐标,如何绘制通过的球体O, A, B, C

答案1

我只是用了一个手持计算器。

\documentclass[tikz,border=2 mm,12pt]{standalone}
\usepackage{tikz-3dplot}
\begin{document} 
    \tdplotsetmaincoords{75}{170} 
    \begin{tikzpicture}[scale=1/10,line cap=butt,line join=round,tdplot_main_coords] 
    \path 
    coordinate (O) at (0, 0, 0) 
    coordinate (A) at (15, -60, 20) 
    coordinate (B) at (96, 120, 128)
    coordinate (C) at (63, 84, 56)
    coordinate (I) at (-98.79, 12.86, 218.29)
    ; 
    \begin{scope}[tdplot_screen_coords]
    \draw[thick] (I) circle (239.94);
    \end{scope}
    ; 
    \draw[thick] (O)--(A) (O)--(B) (O)--(C) (A)--(B) (A)--(C) (B)--(C);
    \end{tikzpicture} 
\end{document}

演示

答案2

如果您的问题是如何消除dimension too large错误,一个可能的答案是:使用fpu

\documentclass[tikz,border=2 mm,12pt]{standalone}
\usepackage{fouriernc}
\usepackage{tikz-3dplot-circleofsphere}
\usetikzlibrary{fpu}
\def\pgfmathsetmacroFPU#1#2{\begingroup%
\pgfkeys{/pgf/fpu,/pgf/fpu/output format=fixed}%
\pgfmathsetmacro{#1}{#2}%
\pgfmathsmuggle#1\endgroup}%

\begin{document} 
    \tdplotsetmaincoords{75}{170} 
    \begin{tikzpicture}[scale=1/10,line cap=butt,line join=round,tdplot_main_coords,
        %declare function={R= 5*sqrt(451369/(14*14));%  }
        ] 
    \pgfmathsetmacroFPU{\myR}{5*sqrt(451369)/14}
    \path 
    coordinate (O) at (0, 0, 0) 
    coordinate (A) at (15, -60, 20) 
    coordinate (B) at (96, 120, 128)
    coordinate (C) at (63, 84, 56)
    coordinate (I) at   (-1383/14, 90/7, 1528/7)
    ; 
    \begin{scope}[tdplot_screen_coords]
     \draw[thick] (I) circle[radius=\myR];
    \end{scope}
    \end{tikzpicture} 
\end{document}

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