I want to change format of x or y number in green box of below graph .
You can change the formatting for an axis using the
should I think work here. This works by adding some basic
If you intend to change the formatting of an axis with linear scale (i.e. "normal" numbers), you can proceed as in Josephs answer, i.e. by modifying the keys with "/pgf/number format/" prefix.
Log-axes however require the
This style requires the most recent pgfplots stable version 1.5.1