Error: Can't convert string to number: Number Null

Error Message

When using the point dispersion sample extension with a geocoded theme, the following error is returned:

"Can't convert string to number: Number Null"


There are unmatched results in your geocoded theme. These unmatched records do not have any shapes associated with them. When the extension tries to get the coordinate values for the feature it gets a Null value, and errors out of its operation.

Solution or Workaround

  1. Open the table for the geocoded theme.
  2. Select the Start editing option under the table menu.
  3. Open the query builder.
  4. Enter the following into the expression box:

    ( [Av_status] = "U" )

  5. Click New Set.
  6. Delete those records from the table.
  7. Select the Stop editing option under the theme menu.
  8. Click yes to save your edits.
  9. Run the point dispersion extension.