Change Y axis on Heatmap

Hello,

I am trying to change the frequency range in the Y axis on the Heatmap to 100000 from 50000, but the plot does not seem to be working to scale to the proper frequency range on the Y axis. I expect the plot to keep the same scale around 20000 for the upper line when I change the upper scale to 100000, but the graph scales the upper line up to 40000. I’m using function Heatmap2DArrayDataSeries() and passing the series data along with TimeFunc() for mapping to X axis and FreqFunc() for mapping to Y axis. I made some changes to FreqFunc(), but it did not change the upper line to 20000. See below for my partial code. Thanks,

    protected override void OnDisplayLoaded()
    {
    ...
    ...
        _dopplersurface.YAxes[0].VisibleRange = YVisibleRange2; // YVisibleRange2 = {0, 100000}
        _surface.UpdateLayout();

    }

    private void PlotData()
    {
    ...
        ...
        heatmap2DArrayDataSeries = new Heatmap2DArrayDataSeries<DateTime, double, double>(_spectrogramBuffer, TimeFunc, FreqFunc);
        HeatmapRenderableSeries = heatmap2DArrayDataSeries;
    }

    double FreqFunc(int iy)
    {
        double FreqDelta = 1.0 / (time_queue[1] - time_queue[0]).TotalSeconds / (FFT_Points / 2.0);
        if (((FFT_Points / 2.0) * FreqDelta / 2) < (double)YVisibleRange2.Max); // FFT_Points = 1024
        {
            FreqDelta = FreqDelta * 2;
        }
        return iy * FreqDelta / 2; // Returns 0 if iy is 0 and 50000 if iy is 512
    }

    DateTime TimeFunc(int ix)
    {
        if (time_queue.Count > (ix * Step))
        {
            DateTime DateTimeTemp1 = time_queue[ix * Step];
            return DateTimeTemp1;
        }
        else
        {
            return time_queue[time_queue.Count - 1];
        }
    }