[gdal-dev] Transform not working

[Jamie Lahowetz]

I'm new to GDAL and am usingthe python bindings. I want to transform a newly
created shapefile from WGS84 to a Lambert Conical Conformal so that I can
calculate the length of the contained polylines. The script exits with no
errors but when I look at the shapefile in arcCatalog I see that the
projection is still WGS84. Any ideas? Also, is there a way to calculate the
length directly from GDAL? Thanks.

import os
try:
    from osgeo import ogr
    from osgeo import osr

except:
    import ogr
    import osr

#~ start driver
driver = ogr.GetDriverByName('ESRI Shapefile')
#~ set workspace
ws = 'C:\\Users\\deadpickle\\
Desktop\\case study\\verify\\'
os.chdir(ws)

#~ check if it exists
if os.path.exists('test.shp'):
    driver.DeleteDataSource('test.shp')

#~ create a new shp
ds = driver.CreateDataSource('test.shp')

#~ create spatref for new shp
source = osr.SpatialReference()
source.SetFromUserInput('WGS84')

#~ create a new data layer
layer = ds.CreateLayer('test',geom_type=ogr.wkbLineString,srs=source)

#~ add an id field
fieldDefn = ogr.FieldDefn('id', ogr.OFTInteger)
layer.CreateField(fieldDefn)

#~ create a geometry
line = ogr.Geometry(ogr.wkbLineString)

#~ get the def of the layer, scheme
featureDefn = layer.GetLayerDefn()

# create a new feature
feature = ogr.Feature(featureDefn)

#~ Read 2006track file
file = open("2006track.csv","r")
file.readline()
lnlist = file.readlines()
for lines in lnlist:
    value = lines.split(",")
    if float(value[1]) == 2:
        print value
        line.AddPoint(float(value[3]),float(value[2]))
        #~ set the field 'ID'
        feature.SetField('id', float(value[1]))

#~ set the geometry for this shp
feature.SetGeometry(line)

# add the feature to the output layer
layer.CreateFeature(feature)

#~ feature = layer.GetFeature(0)
geom = feature.GetGeometryRef()

#~ change projection to lcc
target = osr.SpatialReference()
target.ImportFromProj4('+proj=lcc +lat_1= 33.000000 +lat_2=45.000000
+lat_0=39.000000 +lon_0=-96.000000 +x_0=0.0 +y_0=0.0')
coordtrans = osr.CoordinateTransformation(source, target)

geom.Transform(coordtrans)

# destroy the geometry and feature and close the data source

ds.Destroy()
line.Destroy()
feature.Destroy()
file.close()
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