Is there a way to count the number of vertices of polygons and lines?

Question

In QGIS, is there a way to count the number of vertices of polygons and lines in a given layer, and create a separate field containing these values? I suspect it's a function somewhere in the field calculator but I can't find it.

Answer 1

It is possible to do this with a little bit of python code. I posted the code and the script to count the vertices and add that info to the attribute table here.

Count Number of Vertices in a Layer using QGIS

Answer 2

Look in the vector menu, there is a "extract nodes" tool.

Answer 3

if you or anyone are interested with arcmap , this page - HowTo: Count the vertices for line or polygon features in ArcMap - can help you...

Procedure

1. Right-click the layer to be evaluated in the Table of Contents and click Open 
Attribute Table.
2. From the Table Options drop-down, click Add Field to add a new field to the table.
3. Name the field VxCount and select Long Integer for the field type. Click OK.
4. Right-click the heading of the new field and click Field Calculator.

    The geoprocessing tool, Calculate Field, can also be used to populate the field.

5. Under Parser, select Python.
6. In the main expression box, set:

    VxCount = !shape!.pointcount

7. Click OK.

i hope it helps you...