On 22 January 2018 at 21:18, Paolo Cavallini <cavall...@faunalia.it> wrote: > Hi all, > I have a large shp with a number of repeated strings, and I'd like to > refactor it replacing strings with a numeric code. I have found a > Processing alg that does it, creating a new file each time, which is > cumbersome; moreover, the alg apparently changes field type, adding > decimals to reals. Of course I could create a CASE statement, but this > is also cumbersome. > Is there a more straightforward way? > Thanks.
Two ideas (both based on master, because qgis 2.18 is painful to use now!): Option 1: Run the "Add unique value field index" algorithm to add an autogenerated code for each unique category. Then, run the "List unique values" algorithm selecting both the original field and the newly created field for the "target fields" in order to get a summary table mapping the new categories to their original values (or wait until https://github.com/qgis/QGIS/pull/6132 is merged, which adds creation of this summary table as an option to the alg... then you can do this with a single algorithm execution) Option 2: Run the "List unique values" algorithm on your table, selecting the field to reclass as the "target field". In the returned table (which contains all the unique categories), add a new field for your reclassed codes, and populate this in some way that makes sense for you (e.g. manually, or via field calculator, etc). Then, run the "join attributes table" algorithm and join your original table to the class table, joining by your original field value and adding the new code field as the "layer 2 field to copy". Nyall _______________________________________________ QGIS-Developer mailing list QGIS-Developer@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
