tasks a-s

Task/Plot-coordinate-pairs/XPL0/plot-coordinate-pairs.xpl0

@@ -0,0 +1,34 @@
+include c:\cxpl\codes;          \intrinsic 'code' declarations
+
+def     ScrW=640, ScrH=480, VidMode=$101;
+def     Sx = ScrW/10,           \pixels per horz grid line
+        Sy = ScrH/10,           \pixels per vert grid line
+        Ox = (3+1+1)*8+2,       \offset for horz grid: allow room for "180.0"
+        Oy = ScrH-20;           \offset for vert grid: allow room for labels
+int     X, DataX;
+real    Y, DataY, Gain;
+def     Brown=6, LCyan=11;
+
+[DataX:= [0,   1,    2,    3,    4,    5,     6,     7,     8,     9];
+ DataY:= [2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0];
+
+SetVid(VidMode);
+for X:= 0 to 9 do                                               \draw grid
+        [Move(X*Sx+Ox, Oy);  Line(X*Sx+Ox, Oy-9*Sy, Brown);     \vert lines
+         Move(Ox, Oy-X*Sy);  Line(9*Sx+Ox, Oy-X*Sy, Brown);     \horz lines
+        ];
+Format(3,1);  Attrib(LCyan);                                    \label grid
+Y:= 0.0;
+for X:= 0 to 9 do
+        [Move(X*Sx+Ox-3, Oy+6); IntOut(6, X);                   \X axis
+         Move(0, Oy-X*Sy-7);     RlOut(6, Y);                   \Y axis
+        Y:= Y + 20.0;
+        ];
+Gain:= float(Sy)/20.0;
+Move(DataX(0)*Sx+Ox, Oy-Fix(DataY(0)*Gain));                    \plot points
+for X:= 1 to 9 do
+        Line(DataX(X)*Sx+Ox, Oy-Fix(DataY(X)*Gain), LCyan);
+
+if ChIn(1) then [];                                             \wait for key
+SetVid(3);                                                      \restore text
+]