Bad (and time-varying) WCPS operations results with multi-band coverages

[Piero Campalani]

Petascope seems to provide wrong (and different at every request) results to operations applied on multiband coverages, whether the operation is applied on a single band (it seems to return {0} in any case) or not (weird numbers are returned).

Simple examples on the rgb test coverage:

1. AVG on 1 RGB cell (should return the cell itself?):

   for m in (rgb) return encode(
       trim(m,
           {x:"CRS:1"(200:200),y:"CRS:1"(200:200)}),
       "csv") 
   
   ==> {"242 27 103"}
   
   for m in (rgb) return encode(
       avg(
           trim(m,
               {x:"CRS:1"(200:200),y:"CRS:1"(200:200)})
       ), "csv") 
   
   ==> {"0 8.70018e-313 7.19645e-262"}
   

2. AVG on 1 RGB cell, only the RED band (should return the single value itself):

   for m in (rgb) return encode(
       trim(m,
           {x:"CRS:1"(200:200),y:"CRS:1"(200:200)}),
       "csv") 
   
   ==> {242}
   
   for m in (rgb) return encode(
       avg(
           trim(m,
               {x:"CRS:1"(200:200),y:"CRS:1"(200:200)})
       ), "csv") 
   
   ==> {0}
   

3. ADD over a multiple bands:

   for m in (rgb) return encode(
       trim(m,
           {x:"CRS:1"(200:201),y:"CRS:1"(200:201)}),
       "csv") 
   
   ==> {"242 27 103","242 27 103"}
   
   for m in (rgb) return encode(
       add(
           (float)trim(m,
               {x:"CRS:1"(200:200),y:"CRS:1"(200:201)})
       ), "csv") 
   
   ==> {"7.26573e-262 3.61544e-313 8.49162e-314"}
   ==> {"484 7563062 16"} without (float) cast
   ==> {"484 7563062 0"}  without (float) cast
   

4. ADD over a single band:

   for m in (rgb) return encode(
       trim(m.red,
           {x:"CRS:1"(200:201),y:"CRS:1"(200:201)}),
       "csv") 
   
   ==> {242,242}
   
   for m in (rgb) return encode(
       add(
           (float)trim(m.red,
               {x:"CRS:1"(200:200),y:"CRS:1"(200:201)})
       ), "csv") 
   
   ==> {8.10648e+16}
   

. Multiplication of multi-band results (but maybe this is not implemented at all):

for m in (rgb) return encode(
    (float)trim(m,{x:"CRS:1"(200:200),y:"CRS:1"(200:200)}) *
    (float)trim(m,{x:"CRS:1"(200:200),y:"CRS:1"(200:200)}), "csv") 

==> Error: Could not evaluate rasdaman query: 
'select csv((float)(((m[200:200,200:200])*((float)(m[200:200,200:200]))))) from rgb AS m'
Cause: Error evaluating rasdaman query: 'select csv((float)(((m[200:200,200:200])*((float)(m[200:200,200:200]))))) from rgb AS m