It looks like you need to reproject your shapefiles into a geographic coordinate reference system; in QGIS (v1.8) the Vector > Data Management > Define Projection is the tool you want. Geographic CRS WGS84 is recommended since that's what the GPS system and Google Earth use.
On Saturday, May 4, 2013 11:28:58 AM UTC+5:30, Chandrashekhar Raman wrote: > > need some help from the mapping gurus here. > > I use Tableau public for visualization and was trying to play with the > pre-delimination shapefiles that someone had previously shared on this > thread. > > Now Tableau requires the data in a format of pointid, polygonid, > subpolygonid, latitude and longitude. and i managed to get that from the > .shx after some research on the internet.. but the problem i have is that > for some strange reason the latitude and longitude is not really that > (snapshot below), but rather a set of numbers which nonetheless gives the > recognizable shapes. > > PolygonID SubPolygonID PointID Longitude Latitude AC_NAME 3 1 1 -12.3218 > 1.461258 Hulsoor 3 1 2 -12.32 1.461099 Hulsoor 3 1 3 -12.3199 1.461188 > Hulsoor 3 1 4 -12.3198 1.461478 Hulsoor 3 1 5 -12.3198 1.46177 Hulsoor > 3 1 6 -12.3199 1.461986 Hulsoor > How do i convert these number sets like (-12.3218,1.4612) into real > latitude and longitude.. i suspect something to do with the Co ordinate > reference system. appreciate any help > > again i am quiet sure this something really basic.. much appreciate any > help.. > > > > > On Sat, Apr 20, 2013 at 4:11 PM, Srinivasan Ramani > <[email protected]<javascript:> > > wrote: > >> Let me add that I got through to EC as well... the in charge of the EC's >> GIS related IT work, and he put me through to their software vendor.. who >> put me through to ... a blank wall... >> >> >> >> On Sat, Apr 20, 2013 at 3:29 PM, Shashank <[email protected]<javascript:> >> > wrote: >> >>> To close down one line of enquiry, I believe that georeferencing and >>> vectorising the PDF maps from the NIC GIS server is pointless. >>> >>> I've attached my quick-and-dirty attempt here, and have overlaid the >>> (pre-delimitation) EC assembly constituency shapefile that was dumped on >>> datameet earlier. >>> >>> At both the georeferencing and vectorisation steps, there's a >>> substantial loss of accuracy; at the georeferencing stage because the PDF >>> map and the earlier EC data don't match up properly (there are kinks in one >>> boundary that aren't duplicated in the other) and at the vectorisation >>> stage the actual boundaries in the PDF are very thick, so they could be >>> anywhere within a few tens of kilometres of their actual position. In the >>> case of Bangalore city particularly, this image is unusable. >>> >>> Other potential sources I've tried accessing, only to discover that they >>> also do not have access to up-to-date AC/PC shapefiles, are the Harvard >>> Geospatial Library and CPR. >>> >>> I'd suggest that the only way of getting a useable version of the data >>> is to get the EC to re-release it, ideally under the auspices of the >>> National Data Portal. This is obviously easier said than done. >>> >>> >>> On Wednesday, April 17, 2013 7:01:48 PM UTC+5:30, Sajjad Anwar wrote: >>> >>>> I gave a quick and dirty shot and see the result in the attached image. >>>> It's useless. The image is somehow getting flipped when I polygonize. >>>> The image is partly useless because of the terrible resolution and >>>> colours. >>>> >>>> I'll take some time out and get to it. Will keep you guys posted if >>>> something good happens. >>>> >>>> Cheers, >>>> Sajjad. >>>> >>>> On Wed, Apr 17, 2013 at 3:18 PM, Karthik Shashidhar >>>> <[email protected]> wrote: >>>> > Reviving this thread. >>>> > >>>> > So the maps themselves are available at >>>> > http://gisserver1.nic.in/**ecimaps <http://gisserver1.nic.in/ecimaps> >>>> > >>>> > More specifically the Karnataka Assembly constituency map (pertinent >>>> given >>>> > the upcoming elections) is available at: >>>> > http://gisserver1.nic.in/**ecimaps/ECIPDF/State_ac_map/** >>>> KARNATAKA.pdf<http://gisserver1.nic.in/ecimaps/ECIPDF/State_ac_map/KARNATAKA.pdf> >>>> >>>> > >>>> > I think this is a vectorized PDF, so should be able to be converted >>>> to shape >>>> > files. >>>> > >>>> > And I assume there is enough expertise on this list to do this >>>> conversion. >>>> > Can someone do the necessary conversions and post the data? >>>> > >>>> > Thanks >>>> > Karthik >>>> > >>>> > >>>> > On Wednesday, 28 November 2012 12:19:56 UTC+5:30, megha wrote: >>>> >> >>>> >> Hi everyone, >>>> >> >>>> >> Can anyone here point me to recent enough shape files for MP/MLA >>>> >> constituencies? >>>> >> >>>> >> Thanks, >>>> >> Megha >>>> > >>>> > -- >>>> > For more details about this list >>>> > http://datameet.org/**discussions/ <http://datameet.org/discussions/> >>>> > --- >>>> > You received this message because you are subscribed to the Google >>>> Groups >>>> > "datameet" group. >>>> > To unsubscribe from this group and stop receiving emails from it, >>>> send an >>>> > email to datameet+u...@**googlegroups.com. >>>> > For more options, visit >>>> > https://groups.google.com/**groups/opt_out<https://groups.google.com/groups/opt_out>. >>>> > >>>> >>>> > >>>> > >>>> >>>> >>>> >>>> -- >>>> Sajjad Anwar | W: http://sajjad.in | T: @geohacker >>>> >>> -- >>> For more details about this list >>> http://datameet.org/discussions/ >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "datameet" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected] <javascript:>. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >>> >>> >> >> >> >> -- >> Best Regards, >> Srinivasan V. Ramani , >> Senior Assistant Editor, >> Economic and Political Weekly , >> New Delhi: 110 067 >> 09650855669 >> >> -- >> For more details about this list >> http://datameet.org/discussions/ >> --- >> You received this message because you are subscribed to the Google Groups >> "datameet" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > > -- For more details about this list http://datameet.org/discussions/ --- You received this message because you are subscribed to the Google Groups "datameet" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
