Print() changes results..?

[Fernand0]

Hello, i copied the RSI indicator, and i added 4 lines.
Because of "Print(smaUp[0]);" the indicator changes values. Which is, nonsense..
Whats going on?

protected override void OnBarUpdate()
        {
            Print("--------");
            Print(CurrentBar);
            Print(smaUp[0]);                                                   // this line changes the graphic and the values to negative
            if (CurrentBar == 0)
            {
                down[0]        = 0;
                up[0]        = 0;

                if (Period < 3)
                    Avg[0] = 50;

                return;
            }

            double input0    = Input[0];
            double input1    = Input[1];

            down[0]            = Math.Max(input1 - input0, 0);
            up[0]            = Math.Max(input0 - input1, 0);
            Print(smaUp[0]);                                                   // this line doesn't change a thing

            if (CurrentBar + 1 < Period)
            {
                if (CurrentBar + 1 == Period - 1)
                    Avg[0] = 50;
                return;
            }

            if ((CurrentBar + 1) == Period)
            {
                // First averages
                avgDown[0]    = smaDown[0];
                avgUp[0]    = smaUp[0];
            }
            else
            {
                // Rest of averages are smoothed
                avgDown[0]    = (avgDown[1] * constant3 + down[0]) / Period;
                avgUp[0]    = (avgUp[1] * constant3 + up[0]) / Period;
            }

            double avgDown0    = avgDown[0];
            double value0    = avgDown0 == 0 ? 100 : 100 - 100 / (1 + avgUp[0] / avgDown0);
            Default[0]        = value0;
            Avg[0]            = constant1 * value0 + constant2 * Avg[1];
        }

[NinjaTrader_ChrisL]

Hi Fernand0, thanks for your question.

I made the same thing on my end and I get the same results. Try my version and see what you get compared to the original RSI. If they are the same, there must be something in your edit causing the problem.

I look forward to hearing from you.

[Fernand0]

i didn't change a thing, are you checking the beggining of the chart?
how a Print can change the values?

[NinjaTrader_ChrisL]

Hi Fernand0, thanks for your reply.

A Print can not change the logic of a a script unless it interferes with a statement like so:

if(<condition>)
Print("");
{// code for condition}

Do you get this same problem when you copy the SMA indicator? Also, try this with the latest MNQ contract if possible, MNQ 06-20.

I look forward to hearing from you.

[Fernand0]

I think i caught it..

if (CurrentBar > 0)
{
    Print(smaUp[0]);
}

it changes the values a lot

if (CurrentBar > Period)
{
    Print(smaUp[0]);
}

it changes the values a little bit

if (CurrentBar > Period - 1)
{
    Print(smaUp[0]);
}

it doesn't change the values

I assume smaUp doesn't have any value to return at: CurrentBar < Period. Despite the error it doesn't throw an exception and it works(with wrong values, but it works)

I tried a couple of indicators, RSI was the only one with this problem. I tried MNQ 06-20, still has the same value.
But i tried Simulated Data Feed, and there are no errors

[NinjaTrader_Jim]

Hello Fernand0,

This is Jim, responding on behalf of Chris who is out of the office at this time.

smaUp and smaDown are dependent on the "up" and "down" series which get calculated in OnBarUpdate. If we print out the SMA value before those dependencies are calculated, we can expect the SMA to be calculated without those dependencies. This creates the divergence.

When I test with a print after these dependencies are calculated, I see the results we would expect.

double input0    = Input[0];
double input1    = Input[1];
down[0]            = Math.Max(input1 - input0, 0);
up[0]            = Math.Max(input0 - input1, 0);

if (CurrentBar > 0)
{
    Print(smaUp[0]);
}

I look forward to assisting.