|
Written on: 2011-02-03, 19:38
|
|
menzia@uw.edu
Frederick Menzia
Topic creator
registered since: 07.12.2010
Posts: 4
|
Once you define the boundaries of a patch, how do you work with it. For example, I want to get an average value for the z values inside the patch and also calculate the surface area of the patch. any help would be greatly appreciated.
Cheers,
Fred
|
|
Written on: 2011-02-04, 15:31
|
|
rschlitzer@awi-bremerhaven.de
Reiner Schlitzer
registered since: 24.04.2008
Posts: 179
|
You will not be able to calculate the area of a patch, but you can obtain the average value and standard-deviation for any variable inside a patch.
Do the following:
1. Right-click on the section, choose Extras>Define Patch and click the polygon surrounding your patch;
2. Right-click on the current sample window and choose Derived Variables; in the Choices list select Patches and click Add; again in the Choices list choose the patch you have defined in 1 and click “<<” and OK. Identify any input variable needed by your patch variable (e.g., Section Longitude or Latitude).
3. Right-click on the station map and select Sample Selection Criteria; click on the Range tab, in the Variable combo-box select the Patches variable and set the Acceptable Range to [1, 1]. This will filter the samples and only those will be shown that lie in your patch.
4. In the section window choose a Z variable of your interest and press F4 once the window has been drawn.
Regards, Reiner
|
|
Written on: 2011-02-04, 15:48
|
|
hecinho@gmx.de
Stephan Heckendorff
registered since: 24.04.2008
Posts: 267
|
Hi Frederick,
Check the Statistics dialog for your data window, there you should find the mean z value. To get there, right-click the data window and select Extras -> Statistics.
I cannot think of a way how to obtain the surface area calculation.
Cheers, Stephan
|
