I am trying to patch two rasters with raster calculator but I am not finding the way to work with no-data values.

* Lager@1 has some information I need as first option, this has as no-data -9999 (reading in the properties)

* Lager@2 has the information I want to complete what is nodata in Lager@1


This command does not produce values where Lager@1 is no-data

`("Large@1" != -9999) * "Large@1" + ("Large@1" = -9999) * "Lager@2"`

I would like to avoid or skip the reclasification becase I might have many zeros and I need to perform this with diferrent rasters that might have different no-data formats, for instance Lager@2 has -99999 instead of -9999.

In GRASS this would be an `r.patch` task, but I cannot (or I do not know how to) control the order in the r.patch available in the Processing Toolbox.

`r.patch input= Lager@1, Lager@2 output=Lager@3`

[![Result of patching of two raster maps containing NULLs using the default settings][1]][1] 


  [1]: https://i.sstatic.net/yx8Ne.png