Querying mesh datasets

[katebradbrook]

Can you extract information from SMS grids on a line (e.g. cross-section) or within a user-defined polygon (e.g. average value)?

[John Howlett]

To extract data along a line (e.g. cross-section):

1. Switch to the Map Module
2. Create a coverage
3. Change the coverage type to "Observation"
4. Create a feature arc defining the line / cross-section you would like to extract
5. Choose the menu "Display | Plot Wizard"
6. Select the "Observation Profile" type plot
7. Set the plot options, click OK
8. A plot will now appear
9. If you right click on the plot you can choose "View Values" (copy / paste from spreadsheet) or "Export / Print" (export to clipboard or .txt file)

To extract information within a user-defined polygon, there are a few options:

1. Select "File | Info Options" and turn on Echo to file or Echo window - make sure the info options you are interested in are turned on
2. Use the menu command "Edit | Select with Poly" to select the points you are interested in
3. You can also create a polygon in a coverage, select the polygon, and choose "Feature Objects | Select / Delete Data" to select a specific area of data

Note that not all items display the same information (for example, when you select mesh nodes you will see the min/max/average, but when you select scatter points you will not. If you want to get information on a subset of a scatter set, you may want to:

1. Select the scatter points you are interested in
2. Right click on the scatter set in the project explorer and choose "split"
3. You now have a new scatter set of just the points you are interested in
4. Right click on the data set you are interested in and select "Info" to see statistical information

You could also convert the scatter set to a mesh if you feel that is easier.