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Avoid overwriting of results in for loop

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Turbulence Analysis
Turbulence Analysis on 19 Aug 2020
Commented: KSSV on 19 Aug 2020
Hi,
I intend to save the results of function output defined inside the for loop, actually for each iteration output pushes 1 x 4 files, so, after the 10 iteration I suppose to get 10 x 4.. But somehow it overwrites, hence, I am getting only the value of last iteration.. Please help me resolve this...
output = zeros(10,4);
for f = 1:1:10
if (f>=1) && (f<=9)
fname_strt = 'B0000' ;
elseif (f>=10) && (f<=99)
fname_strt='B000';
elseif (f>=100) && (f<=999)
fname_strt='B00';
else
fname_strt='B0';
end
fname_end = num2str(f);
fname = strcat(fname_strt,fname_end,'.txt');
A=dlmread(fname,'\t',1,0);
sz = [112 98];
x = reshape(A (:,1),sz);
y = reshape(A (:,2),sz);
u = reshape(A (:,3),sz)';
v = reshape(A (:,4),sz)';
x1 = x(:,1);
y1 = y (1,:)';
output=IDvortex(x1,y1,u,v);
end

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Answers (1)

KSSV
KSSV on 19 Aug 2020
Edited: KSSV on 19 Aug 2020
You canmake your output matrix a 3D.
clc; clear all ;
output = zeros(10,4,10);
for f = 1:1:10
if (f>=1) && (f<=9)
fname_strt = 'B0000' ;
elseif (f>=10) && (f<=99)
fname_strt='B000';
elseif (f>=100) && (f<=999)
fname_strt='B00';
else
fname_strt='B0';
end
fname_end = num2str(f);
fname = strcat(fname_strt,fname_end,'.txt');
A=dlmread(fname,'\t',1,0);
sz = [112 98];
x = reshape(A (:,1),sz);
y = reshape(A (:,2),sz);
u = reshape(A (:,3),sz)';
v = reshape(A (:,4),sz)';
x1 = x(:,1);
y1 = y (1,:)';
M = IDvortex(x1,y1,u,v);
output(:,:,f) = M ;
end

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Show 2 older comments
Turbulence Analysis
Turbulence Analysis on 19 Aug 2020
I didn't understand why it pushes error...
Turbulence Analysis
Turbulence Analysis on 19 Aug 2020
I thought below should work, but still it end with error
Unable to perform assignment because the left and right sides have a different number of elements.
output1 = zeros(10,4);
for f = 1:1:10
if (f>=1) && (f<=9)
fname_strt = 'B0000' ;
elseif (f>=10) && (f<=99)
fname_strt='B000';
elseif (f>=100) && (f<=999)
fname_strt='B00';
else
fname_strt='B0';
end
fname_end = num2str(f);
fname = strcat(fname_strt,fname_end,'.txt');
A=dlmread(fname,'\t',1,0);
sz = [112 98];
x = reshape(A (:,1),sz);
y = reshape(A (:,2),sz);
u = reshape(A (:,3),sz)';
v = reshape(A (:,4),sz)';
x1 = x(:,1);
y1 = y (1,:)';
output=IDvortex(x1,y1,u,v);
output1(f)= output;
% a= output(:,1);
% b=output(:,2);
% c=output(:,3);
% d=output(:,4);
% output1(f,:) = [a,b,c,d];
end
KSSV
KSSV on 19 Aug 2020
A = zeros(10,4,10) ;
for i = 1:10
A(:,:,i) = rand(10,4) ;
end
Above is giving any error? No, it will not.
You have to check the dimensions of M. Check it.

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