How to modify the code below so it can loop over certain files rather then 1?

Hi, Below is the code which is reading one csv file I want to modify this code so it will read 100 csv files and produces 100 values of following [xc,yc,Re,a]. Quick modification would be helpful as deadline in an hour.

Code:

XY = dlmread('contours0.137.csv'); 
%
[xc,yc,Re,a] = circfit(XY(:,1),XY(:,2))

% reconstruct circle from data
n=100;
th = (0:n-1)/n*2*pi;
xe = Re*cos(th)+xc; ye = Re*sin(th)+yc;

figure(1),
plot(XY(:,1),XY(:,2),'b*',xe,ye,'r-'),
title(' measured fitted circles')
legend('measured','fitted')
text(xc-Re*0.9,yc,sprintf('center (%g , %g );  R=%g',xc,yc,Re))
% xlabel x, ylabel y 
axis equal

[jessupj]

try a for loop

[muhammad choudhry]

I have applied the for loop here but it is only reading first file and producing only results from the first file. Below is the code:

csvFile = dir("*.csv") ;

N = length(48) ;

for i = 1:N

data = readtable(csvFile(i).name) ;

XY = data

[xc,yc,Re,a] = circfit(XY(:,1),XY(:,2))

% reconstruct circle from data

n=100;

th = (0:n-1)/n*2*pi;

xe = Re*cos(th)+xc; ye = Re*sin(th)+yc;

end

Answer 1

[KSSV]

csvFiles = dir("*.csv") ;
N = length(csvFiles) ; 
C = zeros(N,3) ; 
for i = 1:N
    XY = dlmread(csvFiles(i).name); 
    [xc,yc,Re,a] = circfit(XY(:,1),XY(:,2));
    C(i,:) = [xc yc Re] ; 
    % reconstruct circle from data
    n=100;
    th = (0:n-1)/n*2*pi;
    xe = Re*cos(th)+xc; ye = Re*sin(th)+yc;

    figure(1),
    hold on
    plot(XY(:,1),XY(:,2),'b*',xe,ye,'r-')
end
title(' measured fitted circles')
legend('measured','fitted')
text(xc-Re*0.9,yc,sprintf('center (%g , %g );  R=%g',xc,yc,Re))
% xlabel x, ylabel y 
axis equal

[jessupj]

In the workds of one of your fellow MVP's:

[muhammad choudhry]

Hi,

Please see the attached image. With my code I pasted and with your modified code, I am still only getting one value Re. If you look at workspace you will understand what is it doing. So lets say if I am asking the folder to read all the files in the folder which is 48 hence it should read the data from 48 files and produces 48 values of Re but I am not sure why this is not happening here.

Thanks in advance for the help!

[KSSV]

You will get only one value and that would be the last. Note that you are not saving those values for every loop. You have to intialize a matrix and save all the values.

Example:

A = zeros(5,1) ;
for i = 1:5
    A(i) = rand ;
end

[muhammad choudhry]

What am I doing wrong here? I have no idea! to me it should work and give me values of [xc,yc,re,a] from each file I am asking it to read.

Code:

csvFiles = dir("*.csv") ;

N = length(csvFiles) ;

for i = 1:N

XY = readtable(csvFiles(i).name);

[xc,yc,Re,a] = zeros(48,1)

for i = 1:48

[xc,yc,Re,a] = circfit(XY(:,1),XY(:,2))

[xc,yc,Re,a](i) = rand;

end

% reconstruct circle from data

n=100;

th = (0:n-1)/n*2*pi;

xe = Re.*cos(th)+xc; ye = Re.*sin(th)+yc;

end

Error:

Error: File: test_circlefit.m Line: 12 Column: 14

Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for

mismatched delimiters.

[KSSV]

I have edited the answer.....center and radius of circle is stored in C.