Cfrgtkky

I use the following command to create regular polygons. The 5th argument is there to insert options for styling the polygons. Though the line width is 0.3mm as I set it, it looks like the fill=red option is not accepted.

documentclass{article}

usepackage{amsmath,tikz,tkz-euclide,pgfplots,calculator}



newcommandpolygon[5]

{pgfmathsetmacro{angle}{360/#2}

pgfmathsetmacro{a}{(#2-1)/2}

FLOOR{a}{sol}

pgfmathsetmacro{startangle}{-90 + angle/2}

foreach i in {1,2,...,#2}

{pgfmathsetmacro{x}{startangle + angle*i}

draw[#5] (x:#3) --  (x + angle:#3) -- cycle;

tkzDefPoint(x:#3){A_#2}

tkzDrawPoint(A_#2)}

foreach [count=i] j in {#4}{

pgfmathsetmacro{x}{startangle - angle*(i+sol)}

node[anchor=center] at (x:#3+.3) {$j$};}}



begin{document}

begin{tikzpicture}

draw[line width=0.3mm] (0,0) circle (1);

polygon{6}{1}{A,B,varGamma,varDelta,E,Z}{line width=0.3mm,fill=red}



end{tikzpicture}

end{document}

I don't know if the structure of the command is not allowing any other option.

I am wondering why you don't follow approaches like this

documentclass{article}

usepackage{amsmath,tikz}

usetikzlibrary{shapes}



newcommandpolygon[5]{%

    node[draw,#5,regular polygon,regular polygon sides=#2,minimum size=2*#3cm] (p) {};

    foreach i[count=j] in {#4} {

        path (p.center)--(p.corner j) node[pos=1.2] {$i$};

    }

}



begin{document}

begin{tikzpicture}

draw[line width=0.3mm] (0,0) circle (1);

polygon{6}{1}{A,B,varGamma,varDelta,E,Z}{line width=0.3mm,fill=red}

end{tikzpicture}

end{document}

However, I think you should not define a macro for this.

If you want to follow your way, Kpym has given you the right way: use (0,0) instead of cycle. However, one has to do a bit more. Also, there will be a very thin white line.

documentclass{article}

usepackage{amsmath,tikz,tkz-euclide,pgfplots,calculator}



newcommandpolygon[5]{%

    pgfmathsetmacro{angle}{360/#2}

    pgfmathsetmacro{a}{(#2-1)/2}

    FLOOR{a}{sol}

    pgfmathsetmacro{startangle}{-90 + angle/2}

    foreach i in {1,2,...,#2} {

        pgfmathsetmacro{x}{startangle + angle*i}

        fill[#5] (x:#3) --  (x + angle:#3) -- (0,0);

        draw[#5] (x:#3) --  (x + angle:#3);

        tkzDefPoint(x:#3){A_#2}

        tkzDrawPoint(A_#2)

    }

    foreach [count=i] j in {#4} {

        pgfmathsetmacro{x}{startangle - angle*(i+sol)}

        node[anchor=center] at (x:#3+.3) {$j$};

    }

    foreach i in {1,2,...,#2} {

        pgfmathsetmacro{x}{startangle + angle*i}

        tkzDefPoint(x:#3){A_#2}

        tkzDrawPoint(A_#2)

    }

}



begin{document}

begin{tikzpicture}

draw[line width=0.3mm] (0,0) circle (1);

polygon{6}{1}{A,B,varGamma,varDelta,E,Z}{line width=0.3mm,fill=red}



end{tikzpicture}

end{document}