i have to get similar output as i have uploaded.why my data is getting repeated again and again?

T=readtable('input.csv');
th=[0:1:3]';
for i= 1:size(th)
    reph=T{i,end-1};
    imth=T{i,end};
    result(i)=reph+1i*imth;
end
result_data=result';
for j=1:nume1(th)
    result_data2(:,j)=result_data;
end
data1=[th result_data2];
csvwrite('sample.csv',data1);

my same data is getting repeated again and again

I have read input.csv file

and output should be saved in .csv format and it should exactly look similar to file plot.csv ..

2021a version

Answer 1

[David Hill]

T=readtable('input.csv');
th=[0:1:3]';
result=[th,reshape(T.re+T.im*1i,size(th,1),[])];
csvwrite('sample.csv',result);

[dpb]

In

result=[th,reshape(T.re+T.im*1i,size(th,1),[])];

Can't catenate a double and complex double in an ordinary array; have to convert to cell array to do so...

T.C=complex(T.re,T.im);
result=[num2cell(th) num2cell(reshape(T.C,numel(th),[]))];
writecell(result,'plot.csv')

To reproduce the example file will also have to add the string data for the first line not included in above.

[riki singh]

i have all data in form of which is shown in input.csv file

i have to write a code in such a way that my final output looks like plot.csv file.exact replica of that file

[dpb]

Above does so with the one small task left for you to add the first row into the result cell array before calling writecell.

Only thing I'd suggest to change to generalize would be to replace the hardcoded line

th=[0:1:3]';

with

th=unique(T.Th);

to make the code more general if/when the number of elements in Th changes.

Answer 2

[dpb]

Carrying on from @David Hill's most excellent start,

tT=readtable(websave('input.csv','https://www.mathworks.com/matlabcentral/answers/uploaded_files/1151360/input.csv'));
u=unique(tT.Th);                    % in case number changes in future, be general
tT.C=complex(tT.re,tT.im);          % convenience of short v name
out=[{'Th'} compose('p=%d',u.')];   % the header row for starters
out=[out;num2cell(u) num2cell(reshape(tT.C,numel(u),[]))]; % finish off the output cell array
writecell(out,'plot.csv')           % and save 
type plot.csv

Th,p=0,p=1,p=2,p=3
0,3.2+8i,5.2+9i,9.2-40i,6.2+7.8i
1,5.2+8.5i,6.2+7i,9.2-9.5i,5.2-6.3i
2,4.2+3.2i,7.2+5i,8.2-9.8i,6.23-4.5i
3,6.2+6.3i,8.2+2i,7.2+9.8i,4.2+4.5i

[ramya]

Sir this can't be done with for loops? It will be easy for me to understand

[dpb]

You want something that works or a klunk?

You can recast it however you want but there's no point in having MATLAB and not use it as it's designed to be used. The name is, after all, "MATrix LABoratory" for a reason.

[dpb]

So, if you work thru each line at command line and see what does and refer back to the doc for any function with which you're not familiar, what, specifically do you not understand/don't follow after seeing its result?