Comments on week 4 exercises

  1. When you’re doing a grid analysis, you should make sure that grid “snap” to one raster that this the basis for some of the data (like DEM data for watershed, or NLCD land use data).

    Here’s an example where the two sets of grids don’t quite align.  This can start to develop problems as the analysis develops. Some tools are less predictable when grids don’t align ( or they have in the past). Set this in the tool or model environments.
  2. I couldn’t run lots of models for the modeling exercises, because they were stored on the C drive which wipes itself every time it restarts. You had to follow my instructions about file management.  (save and copy entire folder from C or H to P, reopen it there). ArcGIS will work out of one folder UNLESS you save files or data into other folders or use tools from other folders.  Sometimes this requires you to READ where stuff is going before you save it or run a tool.  It might be a good practice to open the project “options” box before you begin so you can be sure you know where it will be storing stuff.
    1. best practice is to keep ALL data, models, etc in one folder so that you can copy that folder to a new location and it will work.
    2. do not “Save As… “ a project to a location anywhere other than where the current .aprx file is (it looks like a blue folder, but it is NOT a folder. It is just a file that uses all the rest of the folders and files in whatever folder contains it).
    3. If you need to copy something from another project, make a connection to that folder in your current project (catalog pane/folders), add whatever piece you need, copy it to the current project (tool, geodatabase, etc), and then ax the connection so that you don’t accidentally save something to the wrong place.
    4. You have be really careful with folder architecture!
      1. Here is one where the user built a model that uses geodatabases and models from the C drive, but the folder where the project should be wasn’t used. Don’t know the source of the extra, oddly named project folders.
      2. Here is one folder, where geodatabases and toolboxes sit without the project file

        and a bunch of other folders (there should be one to use, the top one only).
      3. Here a user has too many toolboxes going in one project (many people did this), and the only successful model is not in the folder where the project is.  Get help from me early if this kind of problem is developing.  I can teach you what you need to learn to do!