topic Least Cost Path Anomalies in ArcGIS Spatial Analyst Questions https://community.esri.com/t5/arcgis-spatial-analyst-questions/least-cost-path-anomalies/m-p/134400#M11134 <HTML><HEAD></HEAD><BODY><SPAN>I have been running some least cost path analyses on manatee GPS telemetry data using ArcGIS 9.3.1.&nbsp; The goal of this analysis is to create the shortest path between points without the path crossing land.&nbsp; We have tried using a simple cost surface (with water given a low cost and land either given a high cost or set as no data), but we have found the results to be unsatisfactory.&nbsp; The final paths often zigzag through an open water body, rather than taking a straight line path.&nbsp; I have done some testing and have traced these anomalies to the cost backlink raster, which appears to have what I am calling �??chutes�?� where the path is forced to travel north-south or east-west for some distance.&nbsp; This action skews the final path and results in a longer path than expected.&nbsp; I have attached an image that represents the final path and the backlink raster used to create the path.&nbsp; </SPAN><BR /><BR /><SPAN>Additionally, we have tested more complicated or heterogeneous cost surfaces based on bathymetry layers to compare the results.&nbsp; What we have found is that the more complicated the cost surface is, the less dependent the final path is on the backlink raster.&nbsp; For our objective, a simple cost surface is the most appropriate.</SPAN><BR /><BR /><SPAN>Has anyone experienced similar problems using the least cost path?&nbsp; I appreciate any suggestions you may have for working around this problem.</SPAN></BODY></HTML> Wed, 14 Sep 2011 13:52:29 GMT StacieKoslovsky 2011-09-14T13:52:29Z Least Cost Path Anomalies https://community.esri.com/t5/arcgis-spatial-analyst-questions/least-cost-path-anomalies/m-p/134400#M11134 <HTML><HEAD></HEAD><BODY><SPAN>I have been running some least cost path analyses on manatee GPS telemetry data using ArcGIS 9.3.1.&nbsp; The goal of this analysis is to create the shortest path between points without the path crossing land.&nbsp; We have tried using a simple cost surface (with water given a low cost and land either given a high cost or set as no data), but we have found the results to be unsatisfactory.&nbsp; The final paths often zigzag through an open water body, rather than taking a straight line path.&nbsp; I have done some testing and have traced these anomalies to the cost backlink raster, which appears to have what I am calling �??chutes�?� where the path is forced to travel north-south or east-west for some distance.&nbsp; This action skews the final path and results in a longer path than expected.&nbsp; I have attached an image that represents the final path and the backlink raster used to create the path.&nbsp; </SPAN><BR /><BR /><SPAN>Additionally, we have tested more complicated or heterogeneous cost surfaces based on bathymetry layers to compare the results.&nbsp; What we have found is that the more complicated the cost surface is, the less dependent the final path is on the backlink raster.&nbsp; For our objective, a simple cost surface is the most appropriate.</SPAN><BR /><BR /><SPAN>Has anyone experienced similar problems using the least cost path?&nbsp; I appreciate any suggestions you may have for working around this problem.</SPAN></BODY></HTML> Wed, 14 Sep 2011 13:52:29 GMT https://community.esri.com/t5/arcgis-spatial-analyst-questions/least-cost-path-anomalies/m-p/134400#M11134 StacieKoslovsky 2011-09-14T13:52:29Z