2016 Update

Task/Fibonacci-word/ZX-Spectrum-Basic/fibonacci-word.zx

@@ -0,0 +1,35 @@
+10 LET x$="1": LET y$="0": LET z$=""
+20 PRINT "N, Length, Entropy, Word"
+30 LET n=1
+40 PRINT n;" ";LEN x$;" ";
+50 LET s$=x$: LET base=2: GO SUB 1000
+60 PRINT entropy
+70 PRINT x$
+80 LET n=2
+90 PRINT n;" ";LEN y$;" ";
+100 LET s$=y$: GO SUB 1000
+110 PRINT entropy
+120 PRINT y$
+130 FOR n=1 TO 18
+140 LET x$="1": LET y$="0"
+150 FOR i=1 TO n
+160 LET z$=y$+x$
+170 LET p$=x$: LET x$=y$: LET y$=p$
+180 LET p$=y$: LET y$=z$: LET z$=p$
+190 NEXT i
+200 LET x$="": LET z$=""
+210 LET s$=y$: GO SUB 1000
+220 PRINT n+2;" ";LEN y$;" ";entropy
+230 PRINT y$ AND (LEN y$<32)
+240 NEXT n
+250 STOP
+1000 REM Calculate entropy
+1010 LET sourcelen=LEN s$: LET entropy=0
+1020 DIM t(255)
+1030 FOR j=1 TO sourcelen
+1040 LET digit=VAL s$(j)+1: LET t(digit)=t(digit)+1
+1050 NEXT j
+1060 FOR j=1 TO 255
+1070 IF t(j)>0 THEN LET prop=t(j)/sourcelen: LET entropy=entropy-(prop*LN (prop)/LN (base))
+1080 NEXT j
+1090 RETURN