Custom activity streams from fit file messages

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22

I’m trying to create a left/right balance metric as a custom stream from the fit file.
What values do I need to output in the data array to have a “50/50” metric ?
The following code is not showing data in the graph:

{
    let streams = icu.streams;
    let act = icu.activity;

    let gpr_l = streams.get('GPRL').data;
    let gpr_r = streams.get('GPRR').data;

    for (let i = 0; i < gpr_l.length; i++) {
        let sum = gpr_l[i] + gpr_r[i];
        data[i] = (gpr_l[i] / sum) * 100
    }
}
23

There is custom plotting code to handle the built in left_right_balance stream. That stream is stored as “% of right leg” so 65 means 35% from left leg, 65% from right leg displayed as “35/65”. Currently you can’t flag a custom stream as L/R balance to get that display and plot.

Why do you need to recreate L/R balance?

24

It’s not the same L/R balance as the one which is already available.

I’m investigating my L/R imbalance, and for that I created some custom streams (Gross Power Released, Gross Power Absorbed, Net Power Released).
But the L/R balance for GPR and GPA would also be useful to see.

Based on this article: Investigating Power Asymmetry using Pedaling Metrics – Spare Cycles