speedstat

type Bucket struct {
	FromKmh  float64
	ToKmh    float64
	Count    int
	Distance float64 // meters
	Duration float64 // seconds
}

type Histogram struct {
	BinWidth float64
	Buckets  []Bucket

	// Samples are the non-excluded samples, kept for percentile queries.
	Samples []Sample

	TotalDistance float64 // meters
	TotalDuration float64 // seconds

	// Excluded aggregates samples dropped for exceeding Options.MaxSpeedKmh.
	Excluded Bucket
}

type Options struct {
	// MinInterval is the minimum duration a sample must span before its speed
	// is trusted. Shorter spans are merged into the following sample.
	MinInterval time.Duration

	// MinDistance is the minimum distance (in meters) a sample must span
	// before its speed is trusted. Shorter spans are merged into the
	// following sample.
	MinDistance float64

	// MaxHDOP discards points whose horizontal dilution of precision exceeds
	// this value, bridging the gap between the surrounding good fixes. Zero
	// disables HDOP filtering.
	MaxHDOP float64

	// MaxSpeedKmh excludes samples faster than this from the histogram and
	// percentiles, reporting them separately as GPS noise. Zero disables
	// this clamp.
	MaxSpeedKmh float64

	// BinWidth is the histogram bucket width, km/h. Defaults to 5 if zero.
	BinWidth float64
}

type Sample struct {
	SpeedKmh float64
	Distance float64 // meters
	Duration float64 // seconds
}

type WeightFunc func(Sample) float64