How to properly save values into an array when using for loop

Question

I'm trying to push cumDistance into cumDistances array for every iteration of the for loop but I am having trouble.

var inTrade = false
var entry = 0.
var exit = 0.
distance = 0.

entryCon = ta.crossover(ta.rsi(close, 10), 20) and not inTrade
exitCon = ta.crossunder(ta.rsi(close, 10), 80) and inTrade

cumDistances = array.new_float()
for i=1 to 5
    if entryCon[1]
        entry := close[1]
        inTrade := true

    if exitCon[1]
        exit := close[1]
        inTrade := false
        distance := exit - entry*i

    cumDistance = ta.cum(distance)
    array.push(cumDistances, cumDistance)

The values inside the cumDistances array that I get are all the same:

1. -43.41588
2. -43.41588
3. -43.41588
4. -43.41588
5. -43.41588

.

if entryCon[1]
    entry := close[1]
    inTrade := true

if exitCon[1]
    exit := close[1]
    inTrade := false
    distance := exit - entry*i //changed i to 1,2,3,4,5

cumDistance = ta.cum(distance)

If I run the code without for loops(like the code just above), these are the values of cumDistance I get for their respective iteration.

1. 0.02016
2. -10.83885
3. -21.69786
4. -32.55687
5. -43.41588

It seems that the array cumDistances only saves the value of cumDistance for the last iteration of the for loop to all index of the array.

How do I fix this?

EDIT: Response to elod008:

cumDistances = array.new_float()
for i=1 to 5
    var distances = array.new_float()
    if entryCon[1]
        entry := close[1]
        inTrade := true

    if exitCon[1]
        exit := close[1]
        inTrade := false
        distance := exit - entry*i
        array.push(distances, distance)


    cumDistance = array.sum(distances)
    array.push(cumDistances, cumDistance)
    //array.clear(distances) <---- placing this here, I will get NaN,NaN,NaN,NaN,Nan as result

plot(array.size(cumDistances), "no. of index", display=display.data_window)

table1 = table.new(position.top_right, 10, 10)
table.cell(table1, 0, 0, str.tostring(array.get(cumDistances, 0)) + ", "
                         + str.tostring(array.get(cumDistances, 1)) + ", "
                         + str.tostring(array.get(cumDistances, 2)) + ", "
                         + str.tostring(array.get(cumDistances, 3)) + ", "
                         + str.tostring(array.get(cumDistances, 4)))

Answer 1

I ran your code. There seems to be no error in the calculation. What you're experiencing is that ta.cum() works on a series float and sums for you the absolute total as it is supposed to.

However if your conditional that adds new values to the array is false in some iterations, ta.cum() receives n times the default 0.0 of distance, what does not meet your expectations. Your array gets pushed the series cumDistance altered by the built-in function then.

I would not recommend using ta.cum() in this case. I'd rather collect and sum up the relevant results in a var variable/object/matrix etc. depending on your needs.