June 2018 Update

Task/Fibonacci-word/Julia/fibonacci-word.julia

@@ -1,26 +1,27 @@
-# Code for "entropy" taken from https://rosettacode.org/wiki/Entropy#Julia
-entropy(s::String)::Float32 = -sum(x -> x * log(2, x), [count(x -> x == c, s) / length(s) for c in unique(s)])
+using DataStructures
+entropy(s::AbstractString) = -sum(x -> x / length(s) * log2(x / length(s)), values(counter(s)))
 
-function fibboword(n::Int64)::Array{String}
-  # Initialize the result
-  r = Array{String}(n)
-  # First element
-  r[1] = "0"
-  # If more than 2, set the second element
-  if (n ≥ 2)
-    r[2] = "1"
-  end
-  # Recursively create elements > 3
-  for i in 3:n
-    r[i] = r[i - 1] * r[i - 2]
-  end
-  return r
+function fibboword(n::Int64)
+    # Initialize the result
+    r = Array{String}(n)
+    # First element
+    r[1] = "0"
+    # If more than 2, set the second element
+    if n ≥ 2 r[2] = "1" end
+    # Recursively create elements > 3
+    for i in 3:n
+        r[i] = r[i - 1] * r[i - 2]
+    end
+    return r
 end
 
-function testfibbo(n::Int64)
-  fib = fibboword(n)
-  for i in 1:length(fib)
-    println(i, "\t", length(fib[i]), "\t", entropy(fib[i]))
-  end
-  return 0
+function testfibbo(n::Integer)
+    fib = fibboword(n)
+    for i in 1:length(fib)
+        @printf("%3d%9d%12.6f\n", i, length(fib[i]), entropy(fib[i]))
+    end
+    return 0
 end
+
+println("  n\tlength\tentropy")
+testfibbo(37)