Functions

Define reusable functions with function, and custom indicators with indicator. Parameters are type name (use type[] for an array); return hands back a value.

function float midpoint(float h, float l) {
    return (h + l) / 2;
}

indicator float hl2(float h, float l) {
    return (h + l) / 2;
}

onTick {
    float m = midpoint(High(nifty, M5, 0), Low(nifty, M5, 0));
}

Array length — Count()

Count(array) returns the number of elements in an array. Useful for looping over indicator output safely, since the number of values returned can be smaller than you asked for when there is not enough history yet.

float[] swings;
INDICATOR_SWING(swings, nifty, D1, 1, 5);

onTick {
    int n = Count(swings);

    for (int i = 0; i < Count(swings); i = i + 1) {
        // ... use swings[i]
    }
}