2 Replies Latest reply on Jul 27, 2012 8:33 AM by fernandocabral

    "Flow Direction with Streams" difficulties

      I've posted a thread in ArcHydro Forum and while I'm waiting to an answer I keep looking for it in the fora. I didn't find a solution but I found people with the very same problem, from 2009 to 2012!

      If we run the function from ArcHydro Tool Bar the error messages are something like this:

      Flow Direction with Streams
      System.NullReferenceException: Invalid pointer (Exception from HRESULT: 0x80004003 (E_POINTER)) at ESRI.ArcGIS.Geometry.MultipointClass.AddPoint(IPoint inPoint, Object& before, Object& after) at ESRI.APWR.ApHydroOp.FlowDirectionWithStreams(ApLayers apLayers, Double stepsize, Double startElevation, ITrackCancel&trackcancel, IGPMessage& messages, String& exMessage) in C:\Builds\HydroSolutions\10.0_ArcHydro\Sources\ArcHydroTools\src\ApHydro\ArcHydroOp.vb:line 3125

      If we run the function from the ArcHydro Tool Box the problem, in my case, was more serious: I got a VirtualBasic C+++ runtime error saying that I was trying to run a virtual function (something that actually sounded very bad) and the ArcGIS became "non responding". Closing it with ctrl+alt+del made impossible to open the map again! Then, using ctrl+alt+del and restarting the computer I could open the map again, but got the same error message when trying to run the function from the Tool Bar (I wouldn't dare to try to run it from the ArcHydro Tool Box again!)

      Someone, in 2009, complained about these awful error messages but sounded as if he had found a solution: "As this is part of the toolbox rather than the toolbar you have to run the Create Target Locations tool before it will work. Could do with a slightly more helpful error message." The ArcHydro 2.xxx... (used with ArcGIS 10) Tool Bar has a "Set Target Locations" function under ApUtilities; but the help file is not very helpful to give an idea on how to use it to solve this problem.

      ANY HELP AT ALL? Thanks!!!
        • Re: "Flow Direction with Streams" difficulties
          I'm encountering a similar error with my data, any solutions out there or is this another highly specialized set of tools that only works with tutorial data???
          • Re: "Flow Direction with Streams" difficulties

            After that post (seems a long time ago) I managed to do what I needed with "stream definition" and gave up of this "flow direction with streams". I'm dealing with large files (10,000 km2, around 3,000 watersheds) and these "highly speacialized tools", as you mentioned, with very little help, are actually a problem. I believe they have been created to help in complex situations, but we certainly would need to know more about the tools before we could make good use of them, beyond the tutorials. ESRI should give more attention to this before selling expensive licences, as if the ArcGIS was ready for use in highly complex projects. I don't think it is. And some senior GIS technologists in the forum seems to agree with me. If you have time, read the "Delineation of bridges and culverts Watersheds (advanced problems)" in the hydro forum (I've put this same post in different fora and got different answers, all of them very helpfull!) I'm sorry that anything I'm saying is going to help you to solve your specific problem, but maybe it can help you finding other ways to deal with ArcGIS highly specialized tools. I've had success doing so, although I feel that the past 5 months of work could have been done in 5 weeks or less, if ArcGIS/ArcHydro were better finished softwares, with better help files. Good luck!