Hi William,
It looks like you want to move from the limits you have to some with fewer significant figures such as 1 or 2. Here is one possible answer with some functions to try.
function y = roundn(x,n)
% round x to n significant figures.
% rounds toward nearest integer in last significant figure.
% y = roundn(x,n)
logflr = floor(log10(abs(x)));
pof10 = 10.^(n-1-logflr);
y = round(x.*pof10)./pof10;
function y = fixn(x,n)
% round x to n significant figures.
% rounds towards zero.
% y = fixn(x,n)
logflr = floor(log10(abs(x)));
pof10 = 10.^(n-1-logflr);
y = fix(x.*pof10)./pof10;
function y = floorn(x,n)
% round x to n significant figures.
% rounds toward minus inf.
% y = floorn(x,n)
logflr = floor(log10(abs(x)));
pof10 = 10.^(n-1-logflr);
y = floor(x.*pof10)./pof10;
function y = ceiln(x,n)
% round x to n significant figures.
% rounds toward plus inf.
% y = ceiln(x,n)
logflr = floor(log10(abs(x)));
pof10 = 10.^(n-1-logflr);
y = ceil(x.*pof10)./pof10;
