Product and SumCubes

.gitignore

@@ -16,3 +16,4 @@ lumenize.map
 deploy
 .js
 .map
+play

src/functions.coffee

@@ -51,6 +51,25 @@ functions.sum = (values, oldResult, newValues) ->
     temp += v
   return temp
 
+###
+@method product
+@static
+@param {Number[]} [values] Must either provide values or oldResult and newValues
+@param {Number} [oldResult] for incremental calculation
+@param {Number[]} [newValues] for incremental calculation
+@return {Number} The product of the values
+###
+functions.product = (values, oldResult, newValues) ->
+  if oldResult?
+    temp = oldResult
+    tempValues = newValues
+  else
+    temp = 1
+    tempValues = values
+  for v in tempValues
+    temp = temp * v
+  return temp
+
 ###
 @method sumSquares
 @static
@@ -70,6 +89,26 @@ functions.sumSquares = (values, oldResult, newValues) ->
     temp += v * v
   return temp
 
+###
+@method sumCubes
+@static
+@param {Number[]} [values] Must either provide values or oldResult and newValues
+@param {Number} [oldResult] for incremental calculation
+@param {Number[]} [newValues] for incremental calculation
+@return {Number} The sum of the cubes of the values
+###
+functions.sumCubes = (values, oldResult, newValues) ->
+  if oldResult?
+    temp = oldResult
+    tempValues = newValues
+  else
+    temp = 0
+    tempValues = values
+  for v in tempValues
+    temp += v * v * v
+  return temp
+
+
 ###
 @method lastValue
 @static

test/functionsTest.coffee

@@ -175,6 +175,22 @@ exports.functionsTest =
 
     test.done()
 
+  testSumCubes: (test) ->
+
+    test.equal(functions.sumCubes([3]), 27)
+    test.equal(functions.sumCubes([1, 2]), 9)
+    test.equal(functions.sumCubes([0, 5]), 125)
+
+    test.done()
+
+  testProduct: (test) ->
+
+    test.equal(functions.product([3, 7]), 21)
+    test.equal(functions.product([1, 2]), 2) #any number multiplied by 1 is itself
+    test.equal(functions.product([0, 5]), 0) #any number multiplied by 0 is 0
+
+    test.done()
+
   testLastValue: (test) ->
     test.equal(functions.lastValue([0]), 0)
     test.equal(functions.lastValue([]), null) #last value of an empty array is null