Initial data commit

Task/Gray-code/Liberty-BASIC/gray-code.basic

@@ -0,0 +1,55 @@
+    for r =0 to 31
+        print " Decimal "; using( "###", r); " is ";
+        B$ =dec2Bin$( r)
+        print " binary "; B$; ". Binary "; B$;
+        G$ =Bin2Gray$( dec2Bin$( r))
+        print " is "; G$; " in Gray code, or ";
+        B$ =Gray2Bin$( G$)
+        print B$; " in pure binary."
+    next r
+
+    end
+
+    function Bin2Gray$( bin$)   '   Given a binary number as a string, returns Gray code as a string.
+        g$ =left$( bin$, 1)
+        for i =2 to len( bin$)
+            bitA    =val( mid$( bin$, i -1, 1))
+            bitB    =val( mid$( bin$, i,    1))
+            AXorB   =bitA xor bitB
+            g$      =g$ +str$( AXorB)
+        next i
+        Bin2Gray$ =g$
+    end function
+
+    function Gray2Bin$( g$)     '   Given a Gray code as a string, returns equivalent binary num.
+                                '      as a string
+        gl =len(   g$)
+        b$ =left$( g$, 1)
+        for i =2 to len( g$)
+            bitA    =val( mid$( b$, i -1, 1))
+            bitB    =val( mid$( g$, i,    1))
+            AXorB   =bitA xor bitB
+            b$      =b$ +str$( AXorB)
+        next i
+        Gray2Bin$ =right$( b$, gl)
+    end function
+
+    function dec2Bin$( num) '   Given an integer decimal, returns binary equivalent as a string
+        n =num
+        dec2Bin$ =""
+        while ( num >0)
+            dec2Bin$    =str$( num mod 2) +dec2Bin$
+            num         =int( num /2)
+        wend
+        if ( n >255) then nBits =16 else nBits =8
+        dec2Bin$ =right$( "0000000000000000" +dec2Bin$, nBits)  '   Pad to 8 bit or 16 bit
+    end function
+
+    function bin2Dec( b$)   '   Given a binary number as a string, returns decimal equivalent num.
+        t =0
+        d =len( b$)
+        for k =d to 1 step -1
+            t   =t +val( mid$( b$, k, 1)) *2^( d -k)
+        next k
+        bin2Dec =t
+    end function