2

I have a project based on data from a water company, but the arrow heads are all pointing in the wrong direction to indicate the direction of flow. Basically I need to turn all the SYMBOLROTA values to negatives. How can I change all the values of a set of features to become minus - it might be a search function of a script or something?

Better than that would be to be able to change the type of rotation (like you can do in AutoCAD) to be anti-clockwise rather than clockwise. I haven't been able to find out how to do that but that would be the easiest?

3
  • 1
    Welcome to Geographic Information Systems! Welcome to GIS SE! We're a little different from other sites; this isn't a discussion forum but a Q&A site. Your questions should as much as possible describe not just what you want to do, but precisely what you have tried and where you are stuck trying that. Please check out our short tour for more about how the site works.
    – Ian Turton
    Sep 28 '20 at 9:06
  • 1
    Welcome to Geographic Information Systems! what software are you using? Please update your question using the edit button or add a relevant tag.
    – Ian Turton
    Sep 28 '20 at 9:06
  • Please provide a screenshot of you symbology and its settings.
    – Erik
    Sep 28 '20 at 10:00
4

We worked it out - in the attributes table there's a Field Calculator where you can do various calculations based on the data. We selected all the data points and then opened the Field Calculator and updated the existing field (tickbox near top right) and applied the simple calc "SYMBOLROTA" * -1 which just multiplies all the values in the SYMBOLROTA column and puts the answers back in the SYMBOLROTA column replacing the original values.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.