Splitapply command and merge results

In general I am using this command "splitapply" in order to find mean (average) of a group of data.

edges=1:0.5:10
[N, edges, bin] = histcounts(B, edges);
mean_B=splitapply(@mean, B, bin) %mean
%B is 100x1 double 

But I would like to make a code that will :

1) Group my data into bins from edges : 1:0.5:10 (min=1, max=10 with step equal to 0.5)

2) Compute the means of the values in each bin (lets call it set1).

3) Group my data into bins from edges : 2:1:10 (min=2, max=10 with step equal to 1)

4) Compute the means of the values in each bin (set2).

5) Merge two sets of data

Could you please help me in order to make it?

Thanking you in advance

Answer 1

[Rik]

The question for you is what you mean by merging, but steps 1 to 4 are below.

%generate example data
B=10*rand(1,100);

edges1=[1 0.5 10];
edges2=[2 1   10];

mean_B_set1=mean_group_data(B,edges1)

mean_B_set1 = 1×18

1.1522 1.6931 2.2359 2.7160 3.2395 3.8087 4.3454 4.7591 5.2552 5.7937 6.2050 6.7348 7.2927 7.6282 8.2723 8.7246 9.2756 9.7841

mean_B_set2=mean_group_data(B,edges2)

mean_B_set2 = 1×8

2.5560 3.3270 4.5522 5.6142 6.4405 7.5062 8.4984 9.5299

function mean_B=mean_group_data(B,msm)
B(B<msm(1) | B>msm(3))=[];%remove data outside of bounds
edges=msm(1):msm(2):msm(3);
[~, ~, bin] = histcounts(B, edges);
mean_B=splitapply(@mean, B, bin);
if numel(mean_B)<(numel(edges)-1)
    mean_B((end+1):(numel(edges)-1))=NaN;%extend to fill all bins
end
end

[Ivan Mich]

Look for example from the first set I will have 5 bins with 5 mean numbers. From the second set I will have 4 bins with 4 mean numbers. every mean number corresponds to one bin . I am giving you an example of the output

set 1

Bin mean

[2-3] 0.5

[3-4] 1.25

[4-5] 1.6

[5-6] 1.9

[6-7] 3.2

set 2

Bin mean

[2.5-3.5] 0.75

[3.5-4.5] 1

[4.5-5.5] 1.7

[5.5-6.5]2.5

So I mean merge to have an output that will includes all the values.

Like

mean

0.5

0.75

1

1.6

1.7

1.9

2.5

3.2

That's what I mean.

Could you please help me?

[Rik]

That is almost clear. However, your output has 8 numbers, while you started out with 4+5 numbers.

Do you just want to put the all in a vector and sort them, or do you want first a value from set 1, then a value from set 2, then the next from set 1, and so on?

[Ivan Mich]

Excuse me my final output is :

0.5

0.75

1

1.25

1.6

1.7

1.9

2.5

3.2

that corresponds to bins

[2-3]

[2.5-3.5]

[3-4]

[3.5-4.5]

[4-5]

[4.5-5.5]

[5-6]

[5.5-6.5]

[6-7]

[Rik]

Your desired output will be the third column of the array below.

edges1=[2   1 7  ];
edges2=[2.5 1 6.5];
mean_B_set1=[0.5;1.25;1.6;1.9;3.2];
mean_B_set2=[0.75;1;1.7;2.5];

e1=edges1(1):edges1(2):edges1(3);
e2=edges2(1):edges2(2):edges2(3);
%col 1 contains bin starts, col 2 contains bin ends
%col 3 contains the sets
tmp=[e1(1:(end-1)).' e1(2:end).' mean_B_set1;...
    e2(1:(end-1)).' e2(2:end).' mean_B_set2];
output=sortrows(tmp)

output = 9×3

2.0000 3.0000 0.5000 2.5000 3.5000 0.7500 3.0000 4.0000 1.2500 3.5000 4.5000 1.0000 4.0000 5.0000 1.6000 4.5000 5.5000 1.7000 5.0000 6.0000 1.9000 5.5000 6.5000 2.5000 6.0000 7.0000 3.2000