Initial data commit

Task/Metallic-ratios/Factor/metallic-ratios.factor

@@ -0,0 +1,29 @@
+USING: combinators decimals formatting generalizations io kernel
+math prettyprint qw sequences ;
+IN: rosetta-code.metallic-ratios
+
+: lucas ( n a b -- n a' b' ) tuck reach * + ;
+
+: lucas. ( n -- )
+    1 pprint bl 1 1 14 [ lucas over pprint bl ] times 3drop nl ;
+
+: approx ( a b -- d ) swap [ 0 <decimal> ] bi@ 32 D/ ;
+
+: approximate ( n -- value iter )
+    -1 swap 1 1 0 1 [ 2dup = ]
+    [ [ 1 + ] 5 ndip [ lucas 2dup approx ] 2dip drop ] until
+    4nip decimal>ratio swap ;
+
+qw{
+    Platinum Golden Silver Bronze Copper Nickel Aluminum Iron
+    Tin Lead
+}
+[
+    dup dup approximate {
+        [ "Lucas sequence for %s ratio " printf ]
+        [ "where b = %d:\n" printf ]
+        [ "First 15 elements: " write lucas. ]
+        [ "Approximated value: %.32f " printf ]
+        [ "- reached after  %d  iteration(s)\n\n" printf ]
+    } spread
+] each-index