Dimensions of arrays being concatenated are not consistent.

I want to bin the price values in 5 bins and for each bin to group the demand values AND

then calculate the mean and the standard deviation of the demand data for each bin.

Could you please help me to fix the code?

I am trying with the following code but I got this error:

Dimensions of arrays being concatenated are not consistent.

p=Data(:,1);
d=Data(:,2);
partitions = [0 40; 40 55; 55 65; 65 max(x)+1];
for k1 = 1:size(partitions,1)
    ypartmean(k1) = mean(di((pi >= partitions(k1,1)) & (pi < partitions(k1,2))));
    binct(k1) = numel(di((pi >= partitions(k1,1)) & (pi < partitions(k1,2))));
end

Answer 1

[Matt J]

No need to loop,

E=[0,40,65,55,inf];

[binct,~,G]=histcounts(p,E);

ypartmean=splitapply(@mean,d,G);

[Matt J]

My proposed code doesn't use "partitions" anymore. But if you need it for something else, you must ensure that max(x) is a scalar.

[gjashta]

Sorry, I was confused!

how I can calculate d-mean/standard deviation for each bin, now d and mean have different length?

[Steven Lord]

Since you're using the third output from histcounts and not the first, I recommend using discretize instead. From the histcounts documentation page:

"The behavior of histcounts is similar to that of the discretize function. Use histcounts to find the number of elements in each bin. On the other hand, use discretize to find which bin each element belongs to (without counting)."

[Matt J]

Since you Accepted the answer, I assume you figured it out?

[gjashta]

Yes, but I would like to ask you, how I can plot in the same figure but with different colours the observations that belong in the bins, for example, red the observations of bin1, blue observations of bin2, green obserbations of bin3 and black observations of bin4?

[Matt J]

Maybe with a bar plot, as in this example

https://www.mathworks.com/help/matlab/ref/bar.html#d117e77967

[gjashta]

I was looking the example, but I don't want to express the observations as a histogram, just as a data points. I attached one figure for ilustration. I would like to get some data points with different colours.

For example, I am plotting four EPSs, how I can plot them in one figure, but with different colours for their data points.

figure, plot(EPS1,'o');

figure,plot(EPS2,'o');

figure,plot(EPS3,'o');

figure,plot(EPS4,'o');

[Matt J]

Here is an example of how you can give points different colors in a scatter plot

https://www.mathworks.com/help/matlab/ref/scatter.html#btrli6p-1

[gjashta]

I got an error with scatter plot because EPSs above are vectors with different length.

[Matt J]

You certainly should reorganize your data into a form that scatter() expects.