Why not?

src/cmd/map/iplot.h

@@ -0,0 +1,51 @@
+/* Plotting functions for v8 and v9 systems */
+/* This file is an alternative to plot.h */
+
+/* open the plotting output */
+#define openpl()  print("o\n")
+
+/* close the plotting output */
+#define closepl()  print("cl\n")
+
+/* make sure the page or screen is clear */
+#define erase() print("e\n")
+
+/* plot a point at _x,_y, which becomes current */
+#define point(_x,_y)  print("poi %d %d\n", _x,_y)
+
+/* coordinates to be assigned to lower left and upper right
+   corners of (square) plotting area */
+#define range(_x,_y,_X,_Y)  print("ra %d %d %d %d\n", _x,_y,_X,_Y)
+
+/* place text, first letter at current point, which does not change */
+#define text(_s)  {if(*(_s) == ' ')print("t \"%s\"\n",_s); else print("t %s\n", _s); }
+
+/* draw line from current point to _x,_y, which becomes current */
+#define vec(_x,_y)  print("v %d %d\n", _x,_y)
+
+/* _x,_y becomes current point */
+#define move(_x, _y)  print("m %d %d\n", _x, _y)
+
+/* specify style for drawing lines */
+
+#define SOLID "solid"
+#define DOTTED "dotted"
+#define DASHED "dashed"
+#define DOTDASH "dotdash"
+
+#define pen(_s)  print("pe %s\n", _s)
+
+#define BLACK "z"
+#define RED "r"
+#define YELLOW "y"
+#define GREEN "g"
+#define BLUE "b"
+#define CYAN "c"
+#define MAGENTA "m"
+#define WHITE "w"
+
+#define colorcode(_s) ((strcmp(_s,"black")==0)?BLACK:_s)
+
+#define colorx(_s) print("co %s\n", _s);	/* funny name is all ken's fault */
+
+#define comment(s,f)