Dear all,I am working on a python code which gives back the vertices of all polygones within a shape file. Maybe you know the code which already exists in the internet. I have to change it a bit because, it should also write the number of vertices in a line above the vertices. Actually I think my problem is quite simple, however I am not very familiar with programming. So I am going to show you the problem.First of all I want to give you an expression of what the output should be:First polygone with of vertices: n #exterior ring
P1
.
.
Pn
headline with number of vertices of interior ring: m # pf the first polygon
P1
.
.
PmHowever, my output file looks as the following:First polygone with of vertices: n #exterior ring
P1
.
.
Pn
Second polygone with of vertices: n #exterior ring
P1
.
.
Pn
This is the code so far... # step through each vertex in the feature
while pnt:
outLine = str(round((pnt.x), 1)) + " " + str(round((pnt.y), 1)) + "\n" # str(pnt_count)
if sepchar == "": outFile.write(outLine)
else: outFile.write(outLine.replace(".", sepchar))
pnt = part.next()
pnt_count += 1
#If pnt is null, either the part is finished or there is an interior ring.
if not pnt:
pnt = part.next()
if pnt:
pnt_zaehler = 0
while pnt:
pnt = part.next()
pnt_zaehler += 1
pnt_zaehler_neu = pnt_zaehler
outFile.write("interiorRing " + str(rechts) + " " + str(links) + " " + str(vertex) + " pnt_zahler:" +
str (pnt_zaehler) + "\n")
partnum += 1
After writing the outFile ("interiorRing " etc.) I want to go back in the array and want to put out the vertices of the interior ring.As I understand a polygone with interior rings is build up as follow. [[pnt, pnt, pnt], , [pnt, pnt,pnt]]. A space is the end of the exterior ring and the start of the interior ring.In my code above I put a "pnt_zaehler_neu" to count the vertices of the interior ring. This is working. But as it is a while-loop I am going already to the end of the polygon.Therefore, I need to get back to the last beginning of the interior ring that I can put out the vertices again. with an while-loop which I want to put before the row outFile.write ....I hope that my question is cleare and hope that you can give me some help. Thank you very much!
