Data commit

Task/Display-a-linear-combination/Ruby/display-a-linear-combination.rb

@@ -0,0 +1,55 @@
+def linearCombo(c)
+    sb = ""
+    c.each_with_index { |n, i|
+        if n == 0 then
+            next
+        end
+        if n < 0 then
+            if sb.length == 0 then
+                op = "-"
+            else
+                op = " - "
+            end
+        elsif n > 0 then
+            if sb.length > 0 then
+                op = " + "
+            else
+                op = ""
+            end
+        else
+            op = ""
+        end
+        av = n.abs()
+        if av != 1 then
+            coeff = "%d*" % [av]
+        else
+            coeff = ""
+        end
+        sb = sb + "%s%se(%d)" % [op, coeff, i + 1]
+    }
+    if sb.length == 0 then
+        return "0"
+    end
+    return sb
+end
+
+def main
+    combos = [
+        [1, 2, 3],
+        [0, 1, 2, 3],
+        [1, 0, 3, 4],
+        [1, 2, 0],
+        [0, 0, 0],
+        [0],
+        [1, 1, 1],
+        [-1, -1, -1],
+        [-1, -2, 0, -3],
+        [-1],
+    ]
+
+    for c in combos do
+        print "%-15s  ->  %s\n" % [c, linearCombo(c)]
+    end
+end
+
+main()