Cfrgtkky

I want to reproduce the attached figure but I encounter some troubles for the display of labels.

   documentclass[tikz]{standalone}

   usepackage{color}

   tikzset{

    zellige/.pic={

    draw[ultra thick] (0,0)--(3,3)--(4,2)--(6,2)--(4,0)

        --(5,-2)--(4,-2)--(3,-1)--(2,-2)--(1,-2)--cycle; 

    }

     }

   begin{document}

   begin{tikzpicture}

   draw[cyan] (0,-14) grid (42,3);

   foreach i in {0,...,9}

   foreach j in {0,...,3}{

     pic at (4*i,-4*j){zellige};}

       foreach i in {0,...,9}

   foreach j in {10,...,19}{

     node[draw,circle,inner sep=15pt,] at (4*i +2.5,0.1){LARGE j};

    }

   end{tikzpicture}

   end{document}

I would just add the node to the definition of the pic (since pics can take arguments).

documentclass[tikz]{standalone}

tikzset{

    zellige/.pic={

    draw[ultra thick] (0,0)--(3,3)--(4,2)--(6,2)--(4,0)

        --(5,-2)--(4,-2)--(3,-1)--(2,-2)--(1,-2)--cycle; 

    node[draw,circle,inner sep=15pt,font=LARGE] at (2.75,0.25) {#1};  

    }

     }

begin{document}

begin{tikzpicture}

   draw[cyan] (0,-14) grid (42,3);

   foreach i in {0,...,9}

   {foreach j [evaluate=j as k using {int(10+10*j+i)}] in {0,...,3}{

     pic at (4*i,-4*j){zellige=k};}}

end{tikzpicture}

end{document}

As for your comment, I added some vectors. (I do not know what your command vv does.) If you want to use every node/.style and give some nodes extra font information, you could use font and node font.

documentclass[tikz]{standalone}

usepackage{amsmath}

tikzset{

    zellige/.pic={

    draw[ultra thick] (0,0)--(3,3)--(4,2)--(6,2)--(4,0)

        --(5,-2)--(4,-2)--(3,-1)--(2,-2)--(1,-2)--cycle; 

    node[draw,circle,inner sep=15pt,font=LARGE] at (2.75,0.25) {#1};  

    }

     }

begin{document}

begin{tikzpicture}[scale=0.5, every node/.style={transform

shape,node font=LARGE}]

   draw[cyan] (0,-14) grid (42,3);

   foreach i in {0,...,9}

   {foreach j [evaluate=j as k using {int(10+10*j+i)}] in {0,...,3}{

     pic at (4*i,-4*j){zellige=k};}}

   draw[color=red,-latex,very thick] (0,0) 

   node [left,node font=boldmathHuge]{{$vec u$}} -- ++ (12,-8);   

   draw[color=red,-latex,very thick] (20,2) 

   node [left,font=boldmathHuge]{{$vec w$}} -- ++ (12,-8);     

end{tikzpicture}

end{document}

As you see, these vectors are boldface, and Huge does have an impact. And by using transform shape you do not have to add scale=0.5 twice.

It is enough to place the labels in the loop that builds the zelliges.

documentclass[tikz]{standalone}

   usepackage{color}

   tikzset{

    zellige/.pic={

    draw[ultra thick] (0,0)--(3,3)--(4,2)--(6,2)--(4,0)

        --(5,-2)--(4,-2)--(3,-1)--(2,-2)--(1,-2)--cycle; 

    }

     }

   begin{document}

   begin{tikzpicture}

   draw[cyan] (0,-14) grid (42,3);

   foreach i in {0,...,9}{

         foreach j [evaluate=j as lab using int((j+1)*10+i)]in {0,...,3}{

                pic at (4*i,-4*j){zellige};

                node[draw,circle,inner sep=15pt] at (4*i+2.5,-4*j){LARGE lab};}

     }

   end{tikzpicture}

   end{document}