This is the command shptreetst that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
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.
Use shptreetst online using onworks.net services
