[Qgis-user] QgsCoordinateTransform does not get initialized in Qgis 2.10

[Tudorache, Marian]

Hi,

I have an issue with coordinate transformation when I use QgsCoordinateTransform class.
I want to transform a point given on ul_stereographic (see the projection string) to lat and long on GRS80 (see the grs80 string).

The point is
czul_old_ddl = qgis.core.QgsPoint(177309.9337868, -893161.8040887)
After I run the below script I get
Transformed point pt1, pt2: (177310,-893162) (-493719,-701640)
So my point supposed to be in lat and long using decimal degree format.
I verified ",xform.isInitialised() and it is False.

So why QgsCoordinateTransform does not get initialized?
I am using QGIS 2.10.

Thank you,
Marian


ul_stereographic = "+proj=sterea +lat_0=53.5 +lon_0=-76.0 +k=0.9996 +x_0=0.0 +y_0=0.0 +a=6378137 +b=6381816.160744 +ellps=GRS80 +datum=GRS80 +units=m +no_defs"
grs80 = "+proj=longlat +ellps=GRS80 +units=degrees"

print "ul_stereographic ", ul_stereographic
print "grs80 ", grs80

crsSrc = qgis.core.QgsCoordinateReferenceSystem()
crsSrc.createFromProj4(ul_stereographic)
crsDest = qgis.core.QgsCoordinateReferenceSystem()
crsDest.createFromProj4(grs80)

xform = qgis.core.QgsCoordinateTransform()
xform.setSourceCrs(crsSrc)
xform.setDestCRS(crsDest)

czul_old_ddl = qgis.core.QgsPoint(177309.9337868, -893161.8040887)
czul_new_ddl = qgis.core.QgsPoint(-493718.78427, -701639.769759)

pt1 = xform.transform(czul_old_ddl, qgis.core.QgsCoordinateTransform.ForwardTransform)
pt2 = xform.transform(czul_new_ddl, qgis.core.QgsCoordinateTransform.ForwardTransform)
print "Transformed point pt1, pt2:", pt1, pt2



print "QGIS CRS ID:", crsSrc.srsid(), crsDest.srsid()
print "Description:", crsSrc.description(), " - ", crsDest.description()
print "Projection Acronym:", crsSrc.projectionAcronym(), " - ", crsDest.projectionAcronym()
print "Ellipsoid Acronym:", crsSrc.ellipsoidAcronym(), " - ", crsDest.ellipsoidAcronym()
#print "Proj4 String:", crsSrc.toProj4(), " - ", crsDest.toProj4()
print "Is geographic:", crsSrc.geographicFlag(), " - ", crsDest.geographicFlag()
print "Map units:", crsSrc.mapUnits(), " - ", crsDest.mapUnits()

print "xform.isInitialised() ",xform.isInitialised()

print "xform.destCRS() ",xform.destCRS()


#results
#ul_stereographic  +proj=sterea +lat_0=53.5 +lon_0=-76.0 +k=0.9996 +x_0=0.0 +y_0=0.0 +a=6378137 +b=6381816.160744 +units=m +no_defs
#grs80  +proj=longlat +ellps=GRS80 +units=degrees
#Transformed point pt1, pt2: (177310,-893162) (-493719,-701640)
#QGIS CRS ID: 0 0
#Description:   -
#Projection Acronym: sterea  -  longlat
#Ellipsoid Acronym:   -  GRS80
#Is geographic: False  -  False
#Map units: 0  -  2
#xform.isInitialised()  False
#xform.destCRS()  <qgis._core.QgsCoordinateReferenceSystem object at 0x8beb320>

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