How to draw a bar graph from cell array with different size length?

For example, i have a = [{1}; {[3 5]}; {[4 6 7]}; {[3 6 7 9]}]. How do I plot the cell array in one bar graph?

[Walter Roberson]

What would you like the resulting graph to look like?

[Chin]

A bar graph that consist of 4 group. The first group just has 1 column (1), second group consist 2 column (3 & 5), third group consist of (4, 6 & 7) and so on. You can refer to the link below.

http://www.infocaptor.com/img/charts/bar_chart.png

Thank you.

[C.J. Harris]

How would you link the data you have provided to the legend (as shown in your example figure)? In the example groups 3 & 5 have only two bars, but it is clearly item 003 which is missing.

The data you have provided doesn't make it clear which elements are missing from each group - and therefore you run the risk of having very misleading bar colours.

[Chin]

Actually i can plot it using excel but I would like to try it from matlab see it can be done via matlab. Is that possible to append 0 behind the cell array so that a = [{[1 0 0 0]}; {[3 5 0 0]}; {[4 6 7 0]}; {[3 6 7 9]}] and then plot it in grouped bar graph?

Answer 1

[Matt Tearle]

This will extract the values and add zeros to the end, then extract all to a matrix. But are you sure the missing values are always at the end? A safer approach would be to import with NaN placeholders where the values are missing. How are you importing the data?

a = [{1}; {[3 5]}; {[4 6 7]}; {[3 6 7 9]}];
n = max(cellfun(@length,a));
f = @(x) [x,zeros(1,n-length(x))];
a = cellfun(f,a,'UniformOutput',false);

x = cat(1,a{:})
bar(x')

[Chin]

Yes, the missing values is always is in the end, but the resulting graph that for this code is not the graph that i want. I would it to show in first group just contains one bar, second group contains two bar and so on but this resulting graph is vice versa.

[Chin]

I know what is the problem already. I just need to change bar(x') to bar(x) then it will get the result that i want. Thank you so much.

[Matt Tearle]

Oh, yes, sorry I misunderstood which way you wanted them grouped. That's good: bar(x) is even neater than having to transpose.

[Chin]

sorry for another question. now i am facing another problem. if the cell array a = [[{1}; {[3 5]}; {[4 6 7]}; {[3 6 7 9]}] [{3}; {[7 1]}; {[8 2 7]}; {[3 5 7 4]}]]. How do I plot it into two bar graph? Which means that a{1, 1} will have first bar graph while a{1, 2} will have another bar graph. Thank you.

Answer 2

[C.J. Harris]

If you are going to pad out your arrays with zeros you don't even need to define it as a cell array, just use a matrix.

Try this:

a = [1 0 0 0; 3 5 0 0; 4 6 7 0; 3 6 7 9];
bar(a,'group')

[Chin]

However, my result is generated in different size cell array.

Answer 3

[Walter Roberson]

L = max(cellfun(@length, a));
bar( cell2mat( @(V) [V, zeros(1,L-length(V))], a, 'Uniform', 0), 'group' )

[Chin]

when i run this code it said '??? Error using ==> cell2mat

Too many input arguments.'.

[Walter Roberson]

bar( cell2mat( cellfun(@(V) [V, zeros(1,L-length(V))], a, 'Uniform', 0)), 'group' )

[Chin]

thanks. This is correct graph. Besides, now I am plotting another two graph from cell array a = [[{1}; {[3 5]}; {[4 6 7]}; {[3 6 7 9]}] [{3}; {[7 1]}; {[8 2 7]}; {[3 5 7 4]}]]. One is graph is from a{:,1} and the second one is from a{:, 2}. I can plot the bar graph but the bar graph consists of same colour compare to only one graph that can have multiple colour. What I am missing? Thanks again for helping.