[immortality]

I have changed the mesh after setFields command and it now gives an error
.so I like to know if is there a command or way to delete non uniform initial values and set it again after such changes?

[mgdenno]

I am not aware of a utility to reset the fields, however you can just open the text files in the 0 directory and delete the internal fields data so that the file only contains the boundary conditions. In general, I think the approach is to create a copy of the field files before running to setFields to avoid having to do it manually.

[Lieven]

Indeed, as Matthew suggests, make a habit of doing

cp -r 0 0.orig

before modifying the fields in the 0-folder. This will save you a lot of time ;-).
Putting the files back is then simply done as

cp 0.orig/* 0/

Cheers,

L