September 2017 Update

Task/Sorting-algorithms-Radix-sort/Jq/sorting-algorithms-radix-sort-1.jq

@@ -0,0 +1,23 @@
+# Sort the input array;
+# "base" must be an integer greater than 1
+def radix_sort(base):
+  # We only need the ceiling of non-negatives:
+  def ceil: if . == floor then . else (. + 1 | floor) end;
+
+  min as $min
+  | map(. - $min)
+  | ((( max|log) / (base|log)) | ceil) as $rounds
+  | reduce range(0; $rounds) as $i
+      # state: [ base^i, buckets ]
+      ( [1, .];
+        .[0] as $base_i
+        | reduce .[1][] as $n
+            ([];
+             (($n/$base_i) % base) as $digit
+             | .[$digit] += [$n] )
+        | [($base_i * base), (map(select(. != null)) | flatten)] )
+  | .[1]
+  | map(. + $min) ;
+
+def radix_sort:
+  radix_sort(10);

Task/Sorting-algorithms-Radix-sort/Jq/sorting-algorithms-radix-sort-2.jq

@@ -0,0 +1,5 @@
+# Verify that radix_sort agrees with sort
+( [1, 3, 8, 9, 0, 0, 8, 7, 1, 6],
+  [170, 45, 75, 90, 2, 24, 802, 66],
+  [170, 45, 75, 90, 2, 24, -802, -66] )
+| (radix_sort == sort)