cell-array

I have a cell array like this: a = {[1 2 3]; [4 5]; [6 7 8 9]}; and want to insert, for example, 10 to the beginning of every cell to have this: >> a{:} ans = 10 1 2 3 ans = 10 4 5 ans = 10 6 7 8 9 Is it possible to do it without any for loop? You can use CELLFUN with anonymous function: b = cellfun(@(x)[10 x],a,'UniformOutput',0) To answer @tmpearce comment I used a simple script to measure running time: a = {[1 2 3]; [4 5]; [6 7 8 9]}; tic a = cellfun(@(x)[10 x],a,'UniformOutput',0) toc a = {[1 2 3]; [4 5]; [6 7 8 9]}; tic for ii=1:numel(a) a{ii} = [10 a{ii}]; end toc The results: Elapsed

This issue appeared when I was answering this question . It should be some stupid error I am doing, but I can't get what error it is… myMatrix = [22 33; 44 55] Returns: >> subsref(myMatrix, struct('type','()','subs',{{[1 2]}} ) ); ans = 22 44 While using it with cells: myCell = {2 3; 4 5} Returns: >> subsref(myCell,struct('type','{}','subs',{{[1 2]}} ) ); ans = 2 % WHATTT?? Shouldn't this be 2 and 4 Matlab?? Checking the subsref documentation , we see: See how MATLAB calls subsref for the expression: A{1:2} The syntax A{1:2} calls B = subsref(A,S) where S.type='{}' and S.subs={[1 2]}. This

>> C = [{1} {2} ; {'@CF'} {2}] C = [ 1] [2] '@CF' [2] >> whos C Name Size Bytes Class Attributes C 2x2 478 cell How can I convert C into double so that: >> C C = 1 2 NaN 2 I've tried str2double(C) . It returns: NaN NaN NaN NaN Find the non numeric values with isnumeric , queried by cellfun . Use that with logical indexing to extract the numeric values: C = [{1} {2} ; {'@CF'} {2}]; isnum = cellfun(@isnumeric,C); result = NaN(size(C)); result(isnum) = [C{isnum}]; C = [{1} {2} ; {'@CF'} {2}] C = [ 1] [2] '@CF' [2] D = cellfun(@isnumeric,C); C(~D)={nan} C = [ 1] [2] [NaN] [2] cell2mat(C) ans = 1 2

I was surprised today to discover that A = {1,2,3} and B = {1,2,3,} are both valid syntax in MATLAB. I would have expected the second statement to yield an error. As best as I can tell, they produce identical cell arrays ( all([A{:}]==[B{:}]) returns true). Is there a reason the second syntax is allowed? Is this a bug in the parser? Are A and B truly the same? Intriguingly, the following is not allowed: C = {1,2,3,,,} thewaywewalk These are more guesses, rather than an answer. One could check the Symbol reference and find that the comma , can be used as Command or Statement Separator To enter