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Asked by Miguelcm90
on 8 Sep 2013

Dear friends, many thanks for helping me, it was succesfull.

I would like to help me in this task, having the next file as example, I will try to explain with only a reduced number of values of the file.

https://www.dropbox.com/s/y3ehqalm3cxmzuj/x.txt

Below is what I have to start, I would need something what is able to do what is shown in "desired output"

imput: 306,000 305,952 304,683 302,265 300,219 306,000 306,008 304,977 302,450 299,846 306,000 305,962 304,840 302,413 299,812 306,000 306,051 305,051 302,396 299,877 306,000 306,003 304,891 302,163 300,017 306,000 306,004 305,002 301,997 300,186 406,000 406,016 404,943 402,467 400,224 406,000 406,009 404,961 402,483 400,361 406,000 406,014 404,852 402,547 400,287 406,000 406,043 404,990 402,520 400,372 406,000 406,048 405,105 402,425 400,817 406,000 406,034 404,928 402,425 400,623 506,000 506,038 505,182 502,518 500,878 506,000 506,003 505,208 502,728 500,684 506,000 505,971 505,110 502,841 501,118 506,000 505,979 505,083 502,644 500,922 506,000 505,985 505,065 502,942 500,955 506,000 506,062 505,067 502,818 501,280

desired output:

(first 3 rows of all groups of same index) 306,000 305,952 304,683 302,265 300,219 406,000 406,016 404,943 402,467 400,224 506,000 506,003 505,208 502,728 500,684

(second 3 rows of all groups of same index)

306,000 306,008 304,977 302,450 299,846 406,000 406,009 404,961 402,483 400,361 506,000 506,003 505,208 502,728 500,684

(third 3 rows of all groups of same index

306,000 305,962 304,840 302,413 299,812 406,000 406,014 404,852 402,547 400,287 506,000 505,971 505,110 502,841 501,118

fourth 3 rows of all groups of same index

306,000 306,051 305,051 302,396 299,877 406,000 406,043 404,990 402,520 400,372 506,000 505,979 505,083 502,644 500,922

fifth...

306,000 306,003 304,891 302,163 300,017 406,000 406,048 405,105 402,425 400,817 506,000 505,985 505,065 502,942 500,955

sitxh...

306,000 306,004 305,002 301,997 300,186 406,000 406,034 404,928 402,425 400,623 506,000 506,062 505,067 502,818 501,280

The desired output would be if, for instance, in the original file I have 234 indexed in groups of 6 rows, I would like to obtain at the end matrix of 39x5 , and the number of matrix is the length, or the amount of rows that I have per group.

I hope to have been clear. And, anyway, many thanks for your help. It was very useful for me, and I am doing little steps to learn how to program.

I know my question is tricky, but once I have the way, I will understand how it works.

Best Regards and heartfelt thanks

Miguel

*No products are associated with this question.*

Answer by Azzi Abdelmalek
on 8 Sep 2013

Edited by Azzi Abdelmalek
on 9 Sep 2013

Accepted answer

% If `your_array` is your cell array

[a,b]=unique(your_array(:,1),'stable'); n=size(your_array,1)/numel(a); zz=reshape(your_array',size(your_array,2)*n,[])' zz1=reshape(zz,size(zz,1),[],n); out= cell2mat(arrayfun(@(x) zz1(:,:,x),(1:n)','un',0))

%or

[a,b]=unique(your_array(:,1),'stable'); n=size(your_array,1)/numel(a); zz=reshape(your_array',size(your_array,2)*n,[])'; zz1=reshape(zz,size(zz,1),[],n); q=permute(zz1,[2 1 3]); out1=q(:,:)';

Show 1 older comment

Miguelcm90
on 9 Sep 2013

Dear Friend, your help works well,

Now, I would need to do the same as I asked in the question: "how to calculate differences inside an array , looping through a matrix and saving results" I do not want to repeat the question so as not to be repetitive.

I got this answer.

[a,b]=unique(x(:,1),'stable'); b=[b;size(x,1)]; out=nan(size(x)); for k=1:numel(b)-1 i1=b(k)+1; i2=b(k+1)-1; out(i1:i2,:)=bsxfun(@minus,x(i1:i2,:),x(i1-1,:)); end out(isnan(out(:,1)),:)=[]; out=out(:,2:end)

Taking into account the results provided in this wire, below are shown only a sample of them see original file in:

https://www.dropbox.com/s/kpifg9z43x4me39/out.txt

imput :

306 305,952 304,683 302,265 300,219 (1) 406 406,016 404,943 402,467 400,224 (2) 506 506,038 505,182 502,518 500,878 (3) 606 605,983 605,304 602,749 601,037 (4) 706 705,992 705,459 703,378 701,678 (5) 806 806,027 805,31 803,212 801,897 (6) 906 906,015 905,542 903,513 902,139 (7)->jump 306 306,008 304,977 302,45 299,846 (8)<- 406 406,009 404,961 402,483 400,361 (9) 506 506,003 505,208 502,728 500,684 (10) 606 605,999 605,447 603,032 601,458 (11) 706 706,012 705,41 703,335 702,125 (12) 806 806,02 805,462 803,338 801,901 (13) 906 906,014 905,25 903,571 901,725 (14)

desired output: this should be the first group:

100 100,064 100,26 100,202 100,005 (row2-row1) 200 200,086 200,499 200,253 200,659 (row3-row1) 300 300,031 300,621 300,484 300,818 (row4-row1) 400 400,04 400,776 401,113 401,459 (row5-row1) 500 500,075 500,627 500,947 501,678 (row6-row1) 600 600,063 600,859 601,248 601,92 (row7-row1)->jump 100 100,001 99,984 100,033 100,515 (row9-row8)-< 200 199,995 200,231 200,278 200,838 (row10-row8) 300 299,991 300,47 300,582 301,612 (row11-row8) 400 400,004 400,433 400,885 402,279 (row12-row8) 500 500,012 500,485 500,888 502,055 (row13-row8) 600 600,006 600,273 601,121 601,879 (row14-row8)

the calculations, start substracting from the second row the first one. then, the from the third to the first one. as you can see in the output. It is like absolute references in Excel, but, changing this reference to the smallest value of the first columm. This first columnn is not used in the calculations but I think is useful to index the arrays. having the start in the smallest value, and ending the loop in the biggest value found in the columm/array.It would be good if it can be applied for more columms and more rows. I do not know if It is possible. Any help is welcome. I think the code to write , is quite similar as one is shown here.

Thank you very much for your help. and I hope your reply.

Azzi Abdelmalek
on 9 Sep 2013

[a,b]=unique(your_array(:,1),'stable'); n=size(your_array,1)/numel(a); zz=reshape(your_array',size(your_array,2)*n,[])'; zz1=reshape(zz,size(zz,1),[],n); out=cell2mat(arrayfun(@(x) bsxfun(@minus,zz1(2:end,:,x),zz1(1,:,x)),(1:n)','un',0))

Answer by Andrei Bobrov
on 8 Sep 2013

Edited by Andrei Bobrov
on 9 Sep 2013

z=[306.000 305.952 304.683 302.265 300.219 306.000 306.008 304.977 302.450 299.846 306.000 305.962 304.840 302.413 299.812 306.000 306.051 305.051 302.396 299.877 306.000 306.003 304.891 302.163 300.017 306.000 306.004 305.002 301.997 300.186 406.000 406.016 404.943 402.467 400.224 406.000 406.009 404.961 402.483 400.361 406.000 406.014 404.852 402.547 400.287 406.000 406.043 404.990 402.520 400.372 406.000 406.048 405.105 402.425 400.817 406.000 406.034 404.928 402.425 400.623 506.000 506.038 505.182 502.518 500.878 506.000 506.003 505.208 502.728 500.684 506.000 505.971 505.110 502.841 501.118 506.000 505.979 505.083 502.644 500.922 506.000 505.985 505.065 502.942 500.955 506.000 506.062 505.067 502.818 501.280];

out = permute(reshape(z,[],3,size(z,2)),[2 3 1]);

ADD

s = size(z); n = s(1)/numel(unique(z(:,1))); out = reshape(permute(reshape(z,n,[],s(2)),[2 1 3]),s);

ADD 2

m = dlmread('path_your_out.txt'); t=[true;diff(m(:,1)) < 0]; out = m-n(cumsum(t),:); out = out(any(out,2),:);

## 1 Comment

## Andrei Bobrov (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/86614#comment_167922

repeated question