How to get coordinates of line

Question

I am working on Qgis python console. I want to draw a line in the center of two parallel lines..For this purpose firstly i have to store the coordinates of those two lines in a variable so i can apply distance formula to draw line in center of two lines..

Can anybody tell me how to get coordinates of a selected line through python console?

Answer 1

If you have only one line selected you can use this:

select = iface.activeLayer().selectedFeatures()
for feature in select:
    geom = feature.geometry()
    if geom.type() == QGis.Line:        
        feat_geom = geom.asPolyline()
        x=feat_geom[0][0]
        y=feat_geom[0][1]
        print x, y

        #you can also export it as wkt, if you need it for further calculations
        wkt = geom.exportToWkt()
        print wkt

if you have more selected features you can create a list and append the values there.

feat_geom = []
select = iface.activeLayer().selectedFeatures()
for feature in select:
    geom = feature.geometry()
    if geom.type() == QGis.Line:        
        f_geom = geom.asPolyline()

        #create a list of geometries
        feat_geom.append(f_geom)

print feat_geom