processes/shortestpath.py

   1 #!/usr/bin/python
   2
   3 # Author: Stepan Kafka
   4
   5 import os,time,string,sys,Gnuplot,re
   6 from pywps.Process.Process import WPSProcess
   7
   8 class Process(WPSProcess):
   9     def __init__(self):
  10         WPSProcess.__init__(self,
  11                 identifier = "shortestpath",
  12                 title="Shortest path",
  13                 abstract="Find the shortest path on the Trentino SAT network",
  14                 version = "0.2",
  15                 storeSupported = True,
  16                 statusSupported = True,
  17                 grassLocation="alpi")
  18
  19         self.cost = self.addLiteralInput(identifier ="cost",
  20                         title = "Start x coordinate",
  21                         type = type(0.0),
  22                         maxOccurs = 200)
  23         self.coord = self.addLiteralInput(identifier ="coord",
  24                         title = "Points",
  25                         type = type("*"),
  26                         minOccurs =4,
  27                         maxOccurs =200)
  28
  29         self.los = self.addComplexOutput(identifier = "los",
  30                             title = "Resulting output map",
  31                             formats = [{"mimeType":"text/xml"}])
  32
  33     def execute(self):
  34
  35         self.cmd("g.mapset mapset=nico")
  36         self.cmd("g.region -d")
  37         self.status.set(msg="Region setted", percentDone=20)
  38         lpoints=self.coord.value[0].split(",")
  39
  40         #Points are stored in lpoints
  41         #we must find every shortest path between two consecutive point and
  42         #put all together
  43         npoints=len(lpoints)/2
  44         #the number of loop cycle in which shortest path is called is npoints-1
  45         x1=lpoints[0]
  46         y1=lpoints[1]
  47         for i in range(2,2*npoints-1,2):
  48                 x2=lpoints[i]
  49                 y2=lpoints[i+1]
  50                 #Find the shortest path between the two points
  51                 self.cmd("echo ""0 %s %s %s %s"" | v.net.path input=allgpx output=path --o" % (x1,y1,x2,y2))
  52                 #print "echo shortest between"+x1+","+y1+":"+x2+","+y2
  53
  54                 #self.cmd("v.overlay")
  55                 #add to the final path the segment
  56                 #
  57                 x1=x2
  58                 y1=y2
  59
  60         self.status.set(msg="Path created",percentDone=40)
  61         self.cmd("v.out.ascii input=path output=/tmp/grass/app.point format=standard")
  62         i = 0
  63         coords=''
  64         f=open('/tmp/grass/app.point', 'r')
  65         h=f.readlines()
  66         l=len(h)
  67         for i in range(13,l-2):
  68                 #jump to the 13th row
  69                 coords=coords+re.sub(' +',',',h[i].strip())+','
  70         coords=coords.rstrip(',')
  71         f.close();
  72         self.cmd("r.profile input=elevation profile=%s output=/tmp/grass/path.profile" % coords)
  73         self.status.set(msg="Altimetric Profile created",percentDone=60)
  74         g = Gnuplot.Gnuplot()
  75         g.title('Profilo altimetrico del sentiero')
  76         g.xlabel('Distanza percorsa')
  77         g.ylabel('Altitudine')
  78         g('set terminal unknown')
  79         g('set data style lines')
  80         g.plot(Gnuplot.File('/tmp/grass/path.profile', title=None))
  81         g.hardcopy('/tmp/grass/profile.png',terminal = 'png')
  82         self.status.set(msg="Gnuplot image generated",percentDone=70)
  83         self.cmd("v.out.ogr format=GML input=path dsn=out.xml  olayer=path.xml")
  84         self.status.set(msg="Results saved", percentDone=80)
  85
  86
  87         if "out.xml" in os.listdir(os.curdir):
  88             self.los.setValue("out.xml")
  89             return
  90         else:
  91             return "Output file not created"
  92
  93