import graph;
unitsize(.5cm,0.005cm);

real xmin=0,    xmax=12,   xstep=1;
real ymin=4800, ymax=6500, ystep=100;
real[] xi={1,2,3,4,5,6,7,8,9,10};
int[]  yi={5000,5150,5200,5430,5570,5740,5860,6100,6120,6260};
path polygone=graph(xi,yi);
marker croix=marker(scale(2)*cross(4),.6bp+blue);
// draw(polygone,croix);         // points + polygone
   draw(polygone,nullpen,croix); // uniquement les points marqués d'une croix

// La grille... sans les graduations !
xlimits(xmin,xmax);
ylimits(ymin,ymax);
pen pBord=nullpen,
    pGrille=.2mm+linetype("0 "+ string(1mm),offset=0,scale=false,adjust=false);
xaxis(BottomTop,pBord,Ticks("%",Step=5,    step=1,
                                pTick=gray,ptick=pGrille,
                            extend=true));
yaxis(LeftRight,pBord,Ticks("%",Step=500,  step=100,
                                pTick=gray,ptick=pGrille,
                            extend=true));
// Les axes
pen stylo=fontsize(8pt);
// axe horizontal d'équation y=4800
yequals(4800,xmin,xmax+xstep,stylo,
        Ticks(Size=1,end=false,endlabel=false,Step=xstep),
        Arrow);
// axe vertical d'équation x=0
xequals(0,   ymin,ymax+ystep,stylo+red,
        Ticks(Size=1,end=false,endlabel=false,Step=ystep),
        Arrow);

label("$x_i$",(xmax+xstep,ymin),S,stylo);
label("$y_i$",(xmin,ymax+ystep),E,stylo);