Print rectangular grid

grid.ps

%!PS-Adobe-3.0
% %%BoundingBox: 0 0 595 842
/inch {72 mul} def
/cm {2.54 div inch} def

/grid { % stack: grid-size, width, height
    /h exch def
    /w exch def
    /s exch def
    /width  w h lt {w} {h} ifelse def
    /height w h lt {h} {w} ifelse def
    /size s cm def
    /minor 10 def
    /msize size minor div def
    gsave
    % a4
    /offx 595 width size mul sub 2 div def
    /offy 842 height size mul sub 2 div def
    offx offy translate
    0 -30 moveto
    24 scalefont
    setfont  
    height 2 string cvs show
    (x) show
    width 2 string cvs show
    ( \() show
    s 10 string cvs show
    (cm\)) show
    1 setlinewidth

    0 0 moveto
    
    0.6 setgray

    0 1 height minor mul
    {
	/counter exch def
	/y counter msize mul def
	counter minor mod 0 ne {
	    newpath
	    0              y moveto
	    width size mul y lineto
	    closepath
	    stroke
	} if
    } for
    
    0 1 width minor mul
    {
    	/counter exch def
     	/x counter msize mul def
	counter minor mod 0 ne {
     	    newpath
     	    x 0               moveto
     	    x height size mul lineto
     	    closepath
     	    stroke
	} if
    } for

    0 setgray

    0 1 height
    {
	/counter exch def
	/y counter size mul def
	newpath
	0              y moveto
	width size mul y lineto
	closepath
	stroke
    } for

    0 1 width
    {
    	/counter exch def
     	/x counter size mul def
     	newpath
     	x 0               moveto
     	x height size mul lineto
     	closepath
     	stroke
	} for
    grestore
} def

/Helvetica findfont
1 8 4 grid % grid size in cm, width and height (will always print in portrait)
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