Bandmath AVG function with NaN values

msi-sslee · April 10, 2024, 9:57am

Hi!

Does anyone know how the avg() bandmath function works with NaN values?

Marco_EOM · April 10, 2024, 11:57am

If one value is NaN the average value will be NaN.
This is the implementation:

senbox-org/snap-engine/blob/master/snap-core/src/main/java/org/esa/snap/core/jexp/impl/ExtMath.java#L121-L128


      
          public static double mean(final EvalEnv env, final Term[] args) {
              double sum = 0.0;
              final int n = args.length;
              for (Term arg : args) {
                  sum += arg.evalD(env);
              }
              return sum / (double) n;
          }

Marco from EOMasters - Mastering Earth Observation

msi-sslee · April 10, 2024, 12:11pm

Thanks. Is there an mean implementation where the nan values are excluded from the calculation?

Marco_EOM · April 10, 2024, 4:10pm

Unfortunately, there is none.

Marco_EOM · May 1, 2024, 6:02am

Now, there is one. It is implemented in the EOMasters Toolbox.

msi-sslee · May 1, 2024, 6:02pm

Awesome! Thanks Marco.