Store data in cell arrays
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Hello Everyone,
I know the question below is quite stupid but please help as I am not able o find a solution for it. This is a sample array that I have. I want to check the second column of this. The places where I get 1 should be stored together in cell array. As I start scanning the first 4 values get stored in cell array 1 then as the value in second column is 0 I do not store it . Again when I get 1 I should store but in cell array 2. The number of values that I will get is not fixed.
26.81267 1
26.82500 1
26.83733 1
26.86200 1
37.41933 0
37.40700 0
37.39466 0
37.38233 0
27.08400 1
27.07167 1
27.05933 1
27.04700 1
27.02233 1
回答（4 个）
the cyclist
2013-7-17
编辑：the cyclist
2013-7-17
If A is your original array, then
C{1} = A(A(:,2)==1,:);
is a one-element cell array that stores the 9 rows with a zero.
If you only wanted to store the first column, then
C{1} = A(A(:,2)==1,1);
instead.
Andrei Bobrov
2013-7-17
编辑：Andrei Bobrov
2013-7-18
a =[26.81267 1
26.82500 1
26.83733 1
26.86200 1
37.41933 0
37.40700 0
37.39466 0
37.38233 0
27.08400 1
27.07167 1
27.05933 1
27.04700 1
27.02233 1];
l = [true;diff(a(:,2))~=0];
l(l) = a(l,2);
ll = cumsum(l);
out = accumarray(ll(a(:,2)>0),a(a(:,2)>0,1),[],@(x){x});
OR
l = [true;diff(a(:,2))~=0];
d = diff([find(l);size(a,1)+1]);
out = mat2cell(a(a(:,2)>0,1),d(a(l,2)>0),1);
Azzi Abdelmalek
2013-7-17
编辑：Azzi Abdelmalek
2013-7-17
i2=[1 1 0 0 1 1 1 1 0 0 1 1 0 0 0 1 1 0 1];
a=[i2(1) diff(i2)];
idx1=find(a==1);
idx2=find(a==-1);
if numel(idx2)<numel(idx1)
idx2(end+1)=numel(a)+1;
end
out=arrayfun(@(x1,x2) i2(x1:x2),idx1,idx2-1,'un',0)
5 个评论
the cyclist
2013-7-17
Azzi, sometimes I think you only answer questions if they require using arrayfun without uniform output! :-)
Azzi Abdelmalek
2013-7-17
the cyclist, I did not understand what you mean?
the cyclist
2013-7-17
I was just joking that because so many of your answers use arrayfun (and usually without uniform output), I wonder if you specifically look for questions that need that, and only answer those.
Azzi Abdelmalek
2013-7-17
It's true, I 've used arrayfun several times, even when it's not the more efficient solution (because I'm not yet good with accumarray), for 'Uniforme output', it's dictated by each case,"I am not guilty!"
Swapnali Gujar
2013-7-17
You can try below code. This code will give you output as a cell whose first 2 cells will have names as "cell_array1" and "cell_array2", since there are 2 times when 1s appear in your input array in continuation (i.e. first 4 times 1s and next 5 times 1s). Below each column name, you will find respective 1s of each scan.
clc
clear all;
arr = [26.81267 1;
26.82500 1;
26.83733 1;
26.86200 1;
37.41933 0;
37.40700 0;
37.39466 0;
37.38233 0;
27.08400 1;
27.07167 1;
27.05933 1;
27.04700 1;
27.02233 1;
]
size_arr = size(arr);
j=0;
scan = 0;
for i=1:length(arr)
if((arr(i,2)) == 1.000)
j=j+1;
scan=j;
if (i<length(arr)) && (arr((i+1),2) == 1.000)
j = j-1;
end
cell_arr{scan} = strcat('cell_array',num2str(scan)); %creates numbered cell arrays
end
end
%===== Now start storing the values into the cell arrays.
index=1;
columns = length(cell_arr)
k=1;
for i =1:length(arr)
if(((arr(i,2)) == 1.000)) && (k<=columns)
cell_arr(index+1,k) = num2cell(arr(i,2));
index = index+1;
elseif (arr(i,2) == 0.000)&&((arr(i+1,2)) == 1.000)
k = k+1;
index=1;
end
end
%end of file
This will give you output as cell_arr =
'cell_array1' 'cell_array2'
[ 1] [ 1]
[ 1] [ 1]
[ 1] [ 1]
[ 1] [ 1]
[] [ 1]
You may need further processing to access these columns separately as per your need.
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