Set parameters increase in the optimization tool

I'm using the optimization tool to set a model's parameters.

I'd like to change the parameters with only an increase in the first or second decimal place. I do not need more precision in the estimation of these parameters. How can i do that in the optimization tool window called with the command optimtool?

Example: i have a starting point parameters vector x=[1 2 3], with lower and upper bounds, lb=[0 0 0] up=[4 4 4]. i'd like that x takes values as x=[2.1 3.2 3.8] or [2.11 3.22 3.87] and not like x=[2.123 3.224 3.879]

thanks!