使用线性回归将 x 限制在域内

Question

似乎“将 x 限制在域内”不适用于线性回归（与“跳过前 n 个=”相反，但此选项不会产生所需的结果）。下面的代码应该给出第 3、第 4 和第 5 个数据点的线性回归并创建一个斜三角形（在本例中局部正好为 2）。如何解决这个问题？

\documentclass{article}
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}
\usepackage{pgfplotstable}
\usetikzlibrary{shapes.geometric, arrows,calc,decorations,decorations.pathreplacing,
patterns,angles,quotes,intersections}

\begin{filecontents*}{data.txt}
                   x                    y
                   1                    2
                   2                    4
                   3                    6
                   4                    8
                   5                   10
                   6                   12
                   7                   14
                   8                   16
                   9                   18
                  10                   20
                  20                   20
\end{filecontents*}
\usepackage{calculator}
\LOG[10]{2.999}{\loga}
\LOG[10]{5.001}{\logb}
\begin{document}

\pgfplotstableread{data.txt}\IGAIEdata
\pgfplotstableset{
    create on use/nepw_mod/.style={
        create col/copy column from table={data.txt}{nepw}
    }
}
\begin{tikzpicture}
    \begin{loglogaxis}[
        xlabel={$\omega$},
        ylabel={Relative error},
        log basis x=10,
        /pgf/number format/precision=5
        ]
%       \addplot[draw=none,forget plot] table[header=true,skip coords between index={0}{2}, skip coords between index={5}{12},
%y={create col/linear regression}]{data.txt} coordinate [pos=0] (A) coordinate [pos=1] (B);

        \addplot[draw=none,forget plot] table[header=true, restrict x to domain=\loga:\logb,
             y={create col/linear regression={y=y}}]{data.txt} coordinate [pos=0] (A) coordinate [pos=1] (B);
%            
%       \addplot[draw=none,forget plot] table[header=true,skip first n=3,
%            y={create col/linear regression}]{data.txt} coordinate [pos=0] (A) coordinate [pos=1] (B);

        \xdef\slopea{\pgfplotstableregressiona}
        \draw (A) |- (B) node [pos=0.25,anchor=east]{\pgfmathprintnumber{\slopea}};
        \addplot[green,mark=*] table{data.txt};
        \addplot table[restrict x to domain=\loga:\logb]{data.txt};
    \end{loglogaxis}
\end{tikzpicture}
\end{document}