# Cell Function

조회 수: 4 (최근 30일)
James 2011년 10월 3일
I've created a sliding window using the cell function. I used this as I am creating the sliding window for a daily time series of data over a few hundred years. The sliding window is 30 years long and because of leap years each row is a different length. So I now have an array of data that looks like this:
data =
10957x1 double
10957x1 double
10958x1 double
and so on...
I'm unfamiliar with the cell function however as this code was shown to me. How do I now use the data in this series? Whenever I type the command for example:
data (1,1)= 10957x1 double
But I need to do a number of things such as take the mean of each vector in the array, how do I do this?

댓글을 달려면 로그인하십시오.

### 채택된 답변

Wayne King 2011년 10월 3일
x = {randn(1000,1), randn(1000,1), randn(1000,1)};
meanz = cellfun(@mean,x,'UniformOutput',false);
meanz = cell2mat(meanz);
##### 댓글 수: 5이전 댓글 3개 표시이전 댓글 3개 숨기기
Wayne King 2011년 10월 3일
you can use cellfun to do that.
Jan 2011년 10월 3일
@James: Use curly braces to access cell elements:
for 1:n, mean(data{n,1}), end
for 1:n, detrend(data{n,1}), end

댓글을 달려면 로그인하십시오.

### 추가 답변 (5개)

Andrei Bobrov 2011년 10월 3일
data2 = cellfun(@(x){mean(x) detrend(x)},x,'un',0)
data2 = cellfun(@(x)[mean(x);detrend(x)],x,'un',0)
##### 댓글 수: 1이전 댓글 -1개 표시이전 댓글 -1개 숨기기
James 2011년 10월 3일
This just gives me the same problem?
It still outputs it as a cell array, I cant do anything with a vector where all it shows me is:
1x2 double, for every row
How can I extract the data from this as it is not currently usable?
I need to plot graphs of this data using many different functions, not just the ones I've put on here.

댓글을 달려면 로그인하십시오.

Wayne King 2011년 10월 3일
You can use two calls to cellfun and then use cell2mat
data1 = cellfun(@mean,x,'UniformOutput',false);
data1 = cell2mat(data1);
data2 = cellfun(@detrend,x,'UniformOutput',false);
data2 = cell2mat(data2);
##### 댓글 수: 2없음 표시없음 숨기기
Wayne King 2011년 10월 3일
Notice that data2 contains the detrended data as column vectors, which you can plot()
plot(data2)
data1 is a row vector of means
James 2011년 10월 3일
Detrend outputs a new value for each value I have. So at the moment using cell2mat the function just seems to put all 30 year period into one single column. Is there a way to define where the data goes? I have tried this but it doesn't seem to work?
detrendcell = cellfun(@(T32)detrend(T32,'linear'),T32,'un',0);
% detrends the data in each cell
n = numel(detrendcell);
for i=1:n
detrendT(i) = cell2mat(detrendcell(i));
end

댓글을 달려면 로그인하십시오.

Fangjun Jiang 2011년 10월 3일
Since data is a cell array, you need to use {} to reference its element, like data{1}, data{2}, data{3}, etc.
data{1} will be a 10957x1 double array, to reference its element, use data{1}(1), data{1}(100), data{1}(10957), etc.
##### 댓글 수: 0이전 댓글 -2개 표시이전 댓글 -2개 숨기기

댓글을 달려면 로그인하십시오.

James 2011년 10월 3일
close all
clear all
year = cet(:,1);
temp = cet(:,4);
day = cet(:,3);
month = cet(:,2);
% Loads Data from CET asc file and sets vectors
%%Constants and vectors
dates = datenum([year,month,day]);
%%30 Year Periods
StartYear=1772;
EndYear=2009;
Period=30;
T32=cell(EndYear-StartYear-Period+1,1);
for Year=StartYear:(EndYear-Period)
StartCount=datenum(Year,1,1)-datenum(StartYear,1,1)+1;
DataCount=datenum(Year+Period,12,31)-datenum(Year,12,31);
T32{Year-StartYear+1}=temp(StartCount:(StartCount+DataCount),1);
end
%%Detrend, mean etc
meancell = cellfun(@(T32)mean(T32),T32,'un',0);
meanT = cell2mat(meancell);
detrendcell = cellfun(@(T32)detrend(T32,'linear'),T32,'un',0);
n = numel(detrendcell);
for i=1:n
n1 = numel(detrendcell{i});
detrendT(:,i) = cell2mat(detrendcell{i}(1:n1));
end
##### 댓글 수: 2없음 표시없음 숨기기
James 2011년 10월 3일
This is my code and it outputs the error:
??? Cell contents reference from a non-cell array object.
Error in ==> cell2mat at 43
cellclass = class(c{1});
Error in ==> Untitled2 at 63
detrendT(:,i) = cell2mat(detrendcell{i}(1:n1));
Any idea whats wrong with it?
Fangjun Jiang 2011년 10월 3일
Why need meancell = cellfun(@(T32)mean(T32),T32,'un',0)
Can it be meancell = cellfun(@mean,T32,'un',0)

댓글을 달려면 로그인하십시오.

Wayne King 2011년 10월 3일
Why didn't you do what I suggested?
detrendcell = cellfun(@(T32)detrend(T32,'linear'),T32,'un',0);
detrendcell = cell2mat(detrendcell);
By the way, 'linear' is the default option for detrend:
so
detrendcell = cellfun(@detrend,T32,'UniformOutput',false);
detrendcell = cell2mat(detrendcell);
The above returns a matrix whose columns are your detrended series.
Is the same and a bit cleaner.
##### 댓글 수: 5이전 댓글 3개 표시이전 댓글 3개 숨기기
Wayne King 2011년 10월 3일
T32 = T32';
detrendcell = cellfun(@detrend,T32,'UniformOutput',false);
detrendcell = cell2mat(detrendcell);
James 2011년 10월 3일
This returns the error:
??? Error using ==> cat
CAT arguments dimensions are not consistent.
Error in ==> cell2mat at 77
m{n} = cat(2,c{n,:});
Error in ==> Untitled2 at 28
detrendcell = cell2mat(detrendcell)

댓글을 달려면 로그인하십시오.

### 카테고리

Help CenterFile Exchange에서 Line Plots에 대해 자세히 알아보기

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by