If you want to follow existing vector-geometry (trace it), the plug-in traceDigitize is very helpful. Please be keep in mind to set the Snapping-Tolerance (Settings – Snapping Options).
After having QGIS 2.x successfully installed on Fedora 20 (yum install qgis) only the QGIS itself seems to be installed. You may get errors when trying to fetch new Plug-ins (Python!) or you have an nearly empty Raster-menu (without the GDAL-Tools).
In these cases install the following packages with YUM:
Screenshot-example (error): Missing GDAL-Lib – although the menu-items are in place:
After installation of the above mentioned packages everything works fine 🙂 – e.g. hillshade and contour-lines
Have a look at the Blog of Markus Neteler
In case the page is offline (PDF): CompilingQGIS201forFedora19
Mit QGIS 2.0 hat sich der Syntax zum Verknüpfen von Zeichenketten über ein Calculate im Table geändert:
Beispiel neuer Syntax:
concat ('<a href="http://URL/flo/rezeptland.php?FIPS=',"FIPS_CNTRY",'">Link...</a>')
Hinweis (bis 1.8er Version): mittels ||-Funktion
The app GoogleTracks for Android-Smartphones is an easy to use tool for logging GPS-Tracks with your phone – & it allows you to export the Tracks to GPS and KML. So it’s no problem to get your tracks in your GIS-Software.
How-To with QGIS 1.8
- Export your Track to GPX in GoogleTracks on your phone
- Copy the *.gpx on your computer (or by the way mail it from your phone 🙂 )
- You can directly open the GPX in QGIS with „Add vector“
- Attention: GPS-Data is saved in GCS WGS84 ! If you combine it with layers in your national CRS be aware of using the correct transformation-parameters !
Google Tracks in PlayStore: Link
In QGIS it is possible (and it’s recommended) to define the project’s CRS (coordinate system).
For Austria MGI M31 use EPSG Code 31258. See screenshots attached.
Quantum GIS has the option to perform on-the-fly transformation between geodata with different coordinate systems within the data-frame.
When to use it ?
You have geodata referenced in different CRS (Coordinate reference systems) in one project (data frame).
Be aware !
Be aware that every data-layer has a coorect CRS defined and the CRS of the data-frame has to be defined !
Also keep attention whether the correct transformation (parameters!) ist performed.
Convert date-field (as String) to Date (as Date field) – Update ArcGIS 10
Datefield = format ([date_string_field], "dd-mm-yyyy")
Convert date-field (as date) to string (ArcGIS 10)
DatePart ( "yyyy", [UTC_DATE] ) & "-" & DatePart ( "m", [UTC_DATE] ) & "-" & DatePart ( "d", [UTC_DATE] ) = yyyy-m-d