September 2017 Update

Task/Forward-difference/Phix/forward-difference.phix

@@ -0,0 +1,15 @@
+function fwd_diff_n(sequence s, integer order)
+    if order>=length(s) then ?9/0 end if
+    for i=1 to order do
+        for j=1 to length(s)-1 do
+            s[j] = s[j+1]-s[j]
+        end for
+        s = s[1..-2]
+    end for
+    return s
+end function
+
+constant s = {90, 47, 58, 29, 22, 32, 55, 5, 55, 73}
+for i=1 to 9 do
+    ?fwd_diff_n(s,i)
+end for