Getting average of a single row of data

Hi Everyone,

I have a dataset that contains a single row of data with around 700 columns. This data corresponds to six years. The first year is columns 1:113, second year is columns 114:238, third year is columns 239:362 and so on for the six years. I want to calculate the average for each year individually but am having some difficulties. Here is what I have tried so far:

Seg1.average_power(index)=[mean(Seg1.P_wave(1:113));mean(Seg1.P_wave(114:238));mean(Seg1.P_wave(239:362));mean(Seg1.P_wave(363:491));mean(Seg1.P_wave(492:616));mean(Seg1.P_wave(617:747))];

I have calculated the Seg1.P_wave values already, however when I run the code an error statement is returned stating that the index exceeds the matrix dimensions. There is probably a very simple solution to it but my knowledge and experience of Matlab is very limited. Any help would be greatly appreciated.

Answer 1

[the cyclist]

Are you sure that Seg1.P_wave is at least 747 elements long?

What is the result of doing

size(Seg1.P_wave)

?

[David]

Thanks for the response,

Yes that variable is 747 elements long, when I run size(Seg1.P_wave) the resulting output is: 1 747.

Answer 2

[Azzi Abdelmalek]

Seg1=struct('P_wave',num2cell(rand(1,747))); % Example
a=[Seg1.P_wave]
b={a(1:113);a(114:238);a(239:362);a(363:491);a(492:616);a(617:747)}
out=cellfun(@mean,b)

[Azzi Abdelmalek]

There is a difference between

b.m=1:5

%and

c=struct('m',num2cell(1:5))

% numel(b)=1
% numel(c)=5

Answer 3

[David Sanchez]

I think your problem is in:

Seg1.average_power(index)

What's the size of Seg1.average_power?

Make sure you can fit your data into it.

What's that index variable? If you just do ( get rid of index if you can )

Seg1.average_power=[mean(Seg1.P_wave(1:113));...
    mean(Seg1.P_wave(114:238));mean(Seg1.P_wave(239:362));...
    mean(Seg1.P_wave(363:491));mean(Seg1.P_wave(492:616));...
    mean(Seg1.P_wave(617:747))];

you will not have any problem.

[David]

Hi David,

You were right, there was no need having index in the code and it seems to work perfectly without it. Thanks for the help, greatly appreciated.