NAME

       shptreetst - execute a spatial query on an existing spatial index

SYNOPSIS

       shptreetst shapefile [minx miny maxx maxy]

DESCRIPTION

       shptreetst  executes a spatial query on an existing spatial index (.qix), that was created
       by the shptree(1) utility. This utility is useful to understand how a search  of  a  Shape
       data set and its qix index works.

OPTIONS

       shapefile
              The name of the .shp file index.

       minx miny maxx maxy
              Extents to render

EXAMPLE

       shptreetst esp 879827.480246 4317203.699447 884286.289767 4321662.508967

         This new LSB index supports a shapefile with 48 shapes, 4 depth
         shapes 6, node 4, -13702.315770,3973784.599548,1127752.921471,4859616.714055
         shapes 5, node 3, -13702.315770,3973784.599548,614098.064712,4460992.262527
         shapes 1, node 1, -13702.315770,3973784.599548,331587.893495,4241748.814186
         shapes 1, node 0, 141678.278400,3973784.599548,331587.893495,4121164.917599
         shapes 1, node 0, 268807.855447,4193028.047889,614098.064712,4460992.262527
         shapes 1, node 0, 268807.855447,3973784.599548,614098.064712,4241748.814186
         shapes 7, node 4, -13702.315770,4372409.051076,614098.064712,4859616.714055
         shapes 1, node 0, -13702.315770,4372409.051076,331587.893495,4640373.265714
         shapes 3, node 1, -13702.315770,4591652.499417,331587.893495,4859616.714055
         shapes 1, node 0, -13702.315770,4712236.396004,176207.299326,4859616.714055
         shapes 2, node 0, 268807.855447,4372409.051076,614098.064712,4640373.265714
         shapes 3, node 2, 268807.855447,4591652.499417,614098.064712,4859616.714055
         shapes 2, node 0, 424188.449617,4712236.396004,614098.064712,4859616.714055
         shapes 1, node 0, 424188.449617,4591652.499417,614098.064712,4739032.817468
         shapes 2, node 1, 499952.540988,3973784.599548,1127752.921471,4460992.262527
         shapes 2, node 0, 499952.540988,4193028.047889,845242.750254,4460992.262527
         shapes 5, node 3, 499952.540988,4372409.051076,1127752.921471,4859616.714055
         shapes 1, node 1, 499952.540988,4372409.051076,845242.750254,4640373.265714
         shapes 1, node 0, 655333.135158,4372409.051076,845242.750254,4519789.369127
         shapes 1, node 0, 499952.540988,4591652.499417,845242.750254,4859616.714055
         read entire file now at quad box rec 20 file pos 1084
         result of rectangle search was
         8, 10, 36, 37, 38, 39, 42, 46,

       Result:
              The  above output from the shptreetst command tells us that the existing .qix index
              is for a Shape data set that contains 48 shapes; indeed the Shape data set used  in
              this  example,  esp.shp,  contains  48 polygons of Spain. The command also tells us
              that qix file has a quadtree depth of 4.

              Most importantly, the resulting shape IDs (or feature IDs) that were  contained  in
              the  bounding  box that we passed in our example were returned at the bottom of the
              output: "8, 10, 36, 37, 38, 39, 42, 46".  You can use a tool such as QGIS  to  view
              those  feature  IDs  and check what shapes MapServer is querying when a user clicks
              within that bounding box.

SEE ALSO

       shptree(1), shptreevis(1), sortshp(1)

                                           27 June 2023                             shptreetst(1)