round2

Does not work in all cases. Try rounding 3.55 to 1 decimal place and you get 3.5 instead of 3.6

Roundn is in the Mapping Toolbox which costs approximately $1,000.00 for a single user license. It is much simpler; however, it has fewer features and costs $1,000.00. The syntax for using roundn is reproduced from the Mathworks website to help anyone who reads this comment thread. Please let me know if a program with the simple syntax of Roundn would be of benefit to the Matlab Central Users Community.

roundn - Round to multiple of 10n
Syntax

roundn(x,n)
Description

roundn(x,n) rounds each element of x to the nearest multiple of 10n. The variable n must be scalar, and integer-valued. For complex x, the imaginary and real parts are rounded independently. For n = 0, roundn gives the same result as round. That is, roundn(x,0) == round(x).

Guys! Use "roundn" if you want to use a simple MATLAB built-in function.

thanks , it solved my problem

I've added keyword-activated floor, ceil, and fix functionality to this; I don't know how to submit an enhancement to a file acquired here, so I'm just pasting the source below (BSD Lic.)

function z = round2(x,y,swtch)
%ROUND2 rounds number to nearest multiple of arbitrary precision.
% Z = ROUND2(X,Y) rounds X to nearest multiple of Y.
% swtch = 'floor' does the same thing, only towards -inf
% = 'ceil' same, only towards +inf
% = 'fix' same, only towards 0
%
%Example 1: round PI to 2 decimal places
% >> round2(pi,0.01)
% ans =
% 3.14
%
%Example 2: round PI to 4 decimal places
% >> round2(pi,1e-4)
% ans =
% 3.1416
%
%Example 3: round PI to 8-bit fraction
% >> round2(pi,2^-8)
% ans =
% 3.1406
%
%Examples 4-6: round PI to other multiples
% >> round2(pi,0.05)
% ans =
% 3.15
% >> round2(pi,2)
% ans =
% 4
% >> round2(pi,5)
% ans =
% 5
%Examples 7-10: round, floor, ceil, and fix PI to nearest 1/7th
%round2(pi,1/7) % recall that PI ~= 3+1/7...
% ans =
% 3.1429
% round2(pi,1/7,'floor') % ... but is < 3+1/7
% ans =
% 3
% round2(pi,1/7,'ceil')
% ans =
% 3.1429
% round2(pi,1/7,'fix')
% ans =
% 3
%
% See also ROUND, FLOOR, CEIL, FIX.

%% defensive programming
error(nargchk(2,3,nargin))
error(nargoutchk(0,1,nargout))
if numel(y)>1
error('Y must be scalar')
end

%%
if nargin < 3
swtch = '';
end
switch swtch
case 'floor'
z = floor(x/y)*y;
case 'ceil'
z = ceil(x/y)*y;
case 'fix'
z = fix(x/y)*y;
otherwise
z = round(x/y)*y;
end

Mate you're a lifesaver I have been looking for something like this for a while.