Example #1
0
func filterRows(
	rows []string,
	timeOrigin int64, timeDistance int,
	geoOrigin util.GeoPoint, geoDistance int,
) []string {
	withinTimeRange := func(time int64) bool {
		if time < timeOrigin-int64(timeDistance) {
			return false
		}
		if time > timeOrigin+int64(timeDistance) {
			return false
		}
		return true
	}

	pointOrigin := geoOrigin.Point()
	withinGeoRange := func(geo util.GeoPoint) bool {
		distance := pointOrigin.GreatCircleDistance(geo.Point())
		return distance <= float64(geoDistance)/1000
	}

	filterRow := func(s string) (string, bool) {
		row := &util.LogRow{}
		util.StructFromString(s, &row)
		return s, withinTimeRange(row.Timestamp) && withinGeoRange(row.Geo)
	}

	return map_reduce.DoMap(rows, filterRow)
}
// Note: This test involves random logic and therefore may be inconsistent. Reference the seed for repeatability.
func TestRandomGeo(t *testing.T) {
	seed := time.Now().Unix()
	rand.Seed(seed)
	origin := util.GeoPoint{
		Latitude:  TEST_LATITUDE,
		Longitude: TEST_LONGITUDE,
	}
	for i := 0; i < TEST_RANDOM_GEO_RUNS; i++ {
		randGeoPoint := randomGeoPoint(origin, TEST_DISTANCE_M)
		distance := origin.Point().GreatCircleDistance(randGeoPoint.Point())
		if !assert.True(
			t,
			distance <= TEST_DISTNACE_KM,
			fmt.Sprintf(
				"The random point %v is %f kms away from the test origin. Seed: %d.",
				randGeoPoint,
				distance,
				seed,
			),
		) {
			t.FailNow()
		}
	}
	assert.NotEqual(
		t,
		randomGeoPoint(origin, TEST_DISTANCE_M),
		randomGeoPoint(origin, TEST_DISTANCE_M),
		fmt.Sprintf("Two random points should not be the same. Seed: %d.", seed),
	)
}
Example #3
0
func randomGeoPoint(origin util.GeoPoint, distance int) util.GeoPoint {
	randDistance := rand.Float64() * float64(distance) / 1000
	randBearing := rand.Float64()*360 - 180
	point := origin.Point()
	newPoint := point.PointAtDistanceAndBearing(randDistance, randBearing)
	return util.NewGeoPoint(newPoint)
}