On 12/16/2011 05:00 PM, Ramon Andiñach wrote: > > On 17/12/2011, at 01:44 , Robert Peck wrote: > >> Hello, >> >> Uncle! I need help. >> >> I have been trying to learn QuantumGIS so that I can put GPS (NAD 83 datum) >> locations of rock outcrops on a USGS quadrangle topographic map (NAD 27 >> datum), connect the points to make contours, and produce a geological map of >> the quadrangle. I know how to make an Excel file into a .csv file which I >> can use to import the data to the project. I have learned how to open a new >> project, load a topo quad map, load a data set, and make either one of them >> visible on the map panel, and that's as far as I get. I'm trying to get the >> data points to appear on the map but am having no success. Below are the >> steps I've taken to get that far. >> >> Any suggestions as to what I'm doing wrong or what I'm not doing right? Any >> assistance will be gratefully appreciated. Thank you, Pilgrim >> >> 1. Open QGIS. >> 2. File >> New Project. >> 3. Layer >> Add Raster Layer >> Browse >> >> Hinton_UTM27z17_nocoll_grey400dpi.tiff >> Open. >> 4. The Hinton,WV USGS quadrangle map appears in the map panel. >> 5. Settings >> Project Properties. >> a. Enable 'on the fly' CRS transformation. >> b. Set CRS to NAD 27/UTM zone 17N (ID 2146). >> c. Hit "apply" and then "OK". >> 6. The map disappears. >> 7. Right click on the Hinton quad layer in the left panel >> Set layer >> CRS >> Set CRS to NAD 27/UTM zone 17N (ID 2146) >> hit "OK". >> 8. The map reappears. >> 9. Layer >> Add delimited text layer >> browse >> >> NRGGPSHINTONAVIS.csv >> Open. >> 10. "Create a layer from a delimited text file" dialog box opens. >> 11. I made sure that "selected delimiters" and "comma" boxes were both >> checked. >> 12. I set X to UTME and Y to UTMN >> hit "OK". >> 13. No data points appear. >> 14. Right click on the data layer >> set layer CRS >> set CRS to NAD >> 83/UTM zone 17N (ID 2294). >> 15. View >> zoom to layer >> data appear but no map. >> 16. If I choose the map layer and go to View >> zoom to layer >> the >> map appears but no data. This goes back and forth with no data points >> appearing on the map, even when the map layer is the bottom layer in the >> layer panel. > > Hi Bob, > > I have a suggestion. I'm not saying that I definitely have the answer. > > The bit of information that we'll need here is how you made the csv file (or > maybe a look at the first few rows of the csv file). > > If you copied the waypoints down manually, then that's probably the right > path, and I'd suggest checking your numbers. > > But, if you downloaded the data from the GPS, then the data is probably not > in NAD 83. > On all of the GPS units I've used, they only display points in the datum you > select. Really they store them in another datum, typically WGS84 (lat-long, > and not projected). You should be able to confirm this by looking in the csv > file (WGS84 would be a small number with lots of decimals, NAD would be a big > number with few decimals). > > And a suggestion to finish with. Try and use an informative subject line > "Help!" doesn't give me any idea if it's something I can help with, but > "problem displaying GPS data" is something I might be able to help with (or > at least make a suggestion :) > > -ramon. >
Yes, I agree if you copied the data via cable from the GPS it is most likely WGS84 Lat/Lon EPSG:4326 However, note that NAD 83 is only a datum, not a coordinate system. If the data was written down by hand on a unit set to display UTM Zone whatever NAD 83 then the statement in the prior email would be correct. If the unit was set to Lat/Lan NAD 83 then it's would actually look the same and only be off by a few meters. So yes, verify what you actually have in your csv. If you're still having trouble I'd be happy to convert it to a shp or gml file for you, and make a quick tutorial video (hmm look online there might be one). Thanks, Alex _______________________________________________ Qgis-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-user
