TRK_SplitByDistanceGap

TRK_SplitByDistanceGap takes a track column and a distance and returns an array of tracks. The result array contains the input track split into segments wherever two vertices are farther apart than the specified distance. The track is split by removing the segment between the two vertices.

The distance can be defined using ST_CreateDistance or with a tuple containing a number and a unit string (e.g., (10, "kilometers")).

Tracks are linestrings that represent the change in an entity's location over time. Each vertex in the linestring has a timestamp (stored as the M-value) and the vertices are ordered sequentially.

For more information on using tracks in GeoAnalytics Engine, see the core concept topic on tracks.

FunctionSyntax
Pythonsplit_by_distance_gap(track, gap_distance)
SQLTRK_SplitByDistanceGap(track, gap_distance)
ScalasplitByDistanceGap(track, gapDistance)

For more details, go to the GeoAnalytics Engine API reference for split_by_distance_gap.

Python and SQL Examples

PythonPythonSQL
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

from geoanalytics.sql import functions as ST
from geoanalytics.tracks import functions as TRK
from pyspark.sql import functions as F

data = [
    ("LINESTRING M (-117.27 34.05 1633455010, -117.22 33.91 1633456062," +\
     " -116.96 33.64 1633457132, -116.85 33.81 1633457224)",),
    ("LINESTRING M (-116.89 33.96 1633575895, -116.71 34.01 1633576982, -116.66 34.08 1633577061)",),
    ("LINESTRING M (-116.24 33.88 1633575234, -116.33 34.02 1633576336)",)
]

df = spark.createDataFrame(data, ["wkt"]).withColumn("track", ST.line_from_text("wkt", srid=4326))

result = df.withColumn("split_by_distance_gap", TRK.split_by_distance_gap("track", (15, "miles")))

ax = result.st.plot("track", edgecolor="lightgrey", linewidths=10, figsize=(15, 8))
result.select(F.explode("split_by_distance_gap")).st.plot(ax=ax, edgecolor="greenyellow", linewidths=3)
ax.legend(['Input track','Result track'], loc='lower right', fontsize='x-large')
Plotted example for TRK_SplitByDistanceGap
Plotted result for TRK_SplitByDistanceGap.

Scala Example

Scala
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

import com.esri.geoanalytics.sql.{functions => ST}
import com.esri.geoanalytics.sql.{trackFunctions => TRK}
import org.apache.spark.sql.{functions => F}

case class lineRow(lineWkt: String)

val data = Seq(lineRow("LINESTRING M (-117.27 34.05 1633455010, -117.22 33.91 1633456062, -116.96 33.64 1633457132)"),
               lineRow("LINESTRING M (-116.89 33.96 1633575895, -116.71 34.01 1633576982, -116.66 34.08 1633577061)"),
               lineRow("LINESTRING M (-116.24 33.88 1633575234, -116.33 34.02 1633576336)"))

val df = spark.createDataFrame(data)
              .withColumn("track", ST.lineFromText($"lineWkt", F.lit(4326)))
              .withColumn("split_by_distance_gap", TRK.splitByDistanceGap($"track",  F.lit(struct(F.lit(15), F.lit("miles")))))
              .withColumn("result_tracks", F.explode($"split_by_distance_gap"))

df.select("result_tracks").show(truncate = false)
Result
1
2
3
4
5
6
7
8
+-------------------------------------------------------------------------------------------------------------------+
|result_tracks                                                                                                      |
+-------------------------------------------------------------------------------------------------------------------+
|{"hasM":true,"paths":[[[-117.27,34.05,1.63345501e9],[-117.22,33.91,1.633456062e9]]]}                               |
|{"hasM":true,"paths":[[[-116.96,33.64,1.633457132e9]]]}                                                            |
|{"hasM":true,"paths":[[[-116.89,33.96,1.633575895e9],[-116.71,34.01,1.633576982e9],[-116.66,34.08,1.633577061e9]]]}|
|{"hasM":true,"paths":[[[-116.24,33.88,1.633575234e9],[-116.33,34.02,1.633576336e9]]]}                              |
+-------------------------------------------------------------------------------------------------------------------+

Version table

ReleaseNotes

1.4.0

Python and SQL functions introduced

1.5.0

Scala function introduced

Your browser is no longer supported. Please upgrade your browser for the best experience. See our browser deprecation post for more details.

You can no longer sign into this site. Go to your ArcGIS portal or the ArcGIS Location Platform dashboard to perform management tasks.

Your ArcGIS portal

Create, manage, and access API keys and OAuth 2.0 developer credentials, hosted layers, and data services.

Your ArcGIS Location Platform dashboard

Manage billing, monitor service usage, and access additional resources.

Learn more about these changes in the What's new in Esri Developers June 2024 blog post.

Close