June 2018 Update

Task/Box-the-compass/Modula-2/box-the-compass.mod2

@@ -0,0 +1,82 @@
+MODULE BoxTheCompass;
+FROM FormatString IMPORT FormatString;
+FROM RealStr IMPORT RealToStr;
+FROM Terminal IMPORT WriteString,WriteLn,Write,ReadChar;
+
+PROCEDURE expand(cp : ARRAY OF CHAR);
+VAR i : INTEGER = 0;
+BEGIN
+    WHILE cp[i] # 0C DO
+        IF i=0 THEN
+            CASE cp[i] OF
+                'N': WriteString("North") |
+                'E': WriteString("East")  |
+                'S': WriteString("South") |
+                'W': WriteString("West")  |
+                'b': WriteString(" by ")
+            ELSE
+                WriteString("-");
+            END;
+        ELSE
+            CASE cp[i] OF
+                'N': WriteString("north") |
+                'E': WriteString("east")  |
+                'S': WriteString("south") |
+                'W': WriteString("west")  |
+                'b': WriteString(" by ")
+            ELSE
+                WriteString("-");
+            END;
+        END;
+        INC(i)
+    END;
+END expand;
+
+PROCEDURE FormatReal(r : REAL);
+VAR
+    buf : ARRAY[0..63] OF CHAR;
+    u,v : INTEGER;
+    w : REAL;
+BEGIN
+    u := TRUNC(r);
+    w := r - FLOAT(u);
+    v := TRUNC(100.0 * w);
+
+    FormatString("%6i.%'02i", buf, u, v);
+    WriteString(buf);
+END FormatReal;
+
+VAR
+    cp : ARRAY[0..31] OF ARRAY[0..4] OF CHAR = {
+        "N", "NbE", "N-NE", "NEbN", "NE", "NEbE", "E-NE", "EbN",
+        "E", "EbS", "E-SE", "SEbE", "SE", "SEbS", "S-SE", "SbE",
+        "S", "SbW", "S-SW", "SWbS", "SW", "SWbW", "W-SW", "WbS",
+        "W", "WbN", "W-NW", "NWbW", "NW", "NWbN", "N-NW", "NbW"
+    };
+    buf : ARRAY[0..63] OF CHAR;
+    i,index : INTEGER;
+    heading : REAL;
+BEGIN
+    WriteString("Index  Degrees  Compass point");
+    WriteLn;
+    WriteString("-----  -------  -------------");
+    WriteLn;
+    FOR i:=0 TO 32 DO
+        index := i MOD 32;
+        heading := FLOAT(i) * 11.25;
+        CASE i MOD 3 OF
+            1: heading := heading + 5.62; |
+            2: heading := heading - 5.62;
+        ELSE
+            (* empty *)
+        END;
+        FormatString("%2i  ", buf, index+1);
+        WriteString(buf);
+        FormatReal(heading);
+        WriteString("   ");
+        expand(cp[index]);
+        WriteLn
+    END;
+
+    ReadChar
+END BoxTheCompass.