Global Mapper v25.0

APPLY FORMULA ouput no-data(void)

suzuki
suzuki Global Mapper User
is it possible to asign a "no-data(void)" output when using the Raster Calculator FORMULA
for example :

     if(B1<0,"no-data",B1)

  when B1 value smaller then 0 asign to no-data(void)

Answers

  • JeffH@BMG
    JeffH@BMG Global Mapper Developer Trusted User
    edited May 2016 Answer ✓
    Hi Suzuki,

    My question would be "what should the value 'no-data' be"? Since we're dealing with gridded data (raster/elevation), we're processing every point in the grid, and we'd expect to store something back to each point. Is there a known value of "no-data" that would apply to all cases? My guess is that there isn't, and that would mean that the answer to your question is that it's not possible in general, although the user may know, for a particular band, what a valid value of "no-data" should be, and they would then plug that into the formula.

    On the other hand, it's also possible that I'm not understanding what you're trying to do, so I'f I'm mistaken, I hope that you'll help me to understand.

    Best regards,

    ~Jeff