Changing a CSV file while keeping it readable by MATLAB

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I have a CSV file (see attached) that I want to make alterations to, but I want to save it in the same format that it's already in. What I do is open the file using the following code (so that it's applicable to different file types):
A = fopen(x)
raw=fread(A)
fclose(A)
str=char(raw')
This produces a 1-by-n cell array that I can work with. All good, I do my changes, but then I can't save it in the same format. I can't use csvwrite because it's not in matrix format. I can use xlswrite to write it as a new CSV file, but when I use the above code to fopen it, the char conversion produces gibberish, with stuff like " @ þCúíëÀõ? ", even though it's a CSV file and looks similar to the original. How can I change the CSV while keeping it useable so that the fopen-fread-char routine still works? Thanks.
  2 Comments
Stephen23
Stephen23 on 8 Nov 2018
Edited: Stephen23 on 8 Nov 2018
"...I do my changes, but then I can't save it in the same format"
It sounds like maybe you are changing the file encoding. Please attach one of the altered files which import incorrectly.

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Accepted Answer

Stephen23
Stephen23 on 9 Nov 2018
Edited: Stephen23 on 9 Nov 2018
'but then I can't save it in the same format.'
Yes, you can.
'I can't use csvwrite because it's not in matrix format.'
That seems possible.
'I can use xlswrite to write it as a new CSV file, but when I use the above code to fopen it, the char conversion produces gibberish, with stuff like " @ þCúíëÀõ? ", even though it's a CSV file and looks similar to the original.'
Nope. It is certainly not a CSV file. What you created (attached) is actually a binary Excel .xls file with the file extension .csv. So nothing like a CSV text file at all. I just changed the file extension and it opened as a perfect .xls file.
'How can I change the CSV while keeping it useable so that the fopen-fread-char routine still works? Thanks.'
By writing a text file, not a binary .xls file.

More Answers (1)

KSSV
KSSV on 8 Nov 2018
[num,txt,T] = xlsread('C:\Users\srinivas\Downloads\Crayford01092018103600.csv') ;
T = readtable('C:\Users\srinivas\Downloads\Crayford01092018103600.csv') ;
Use either xlsread or readtable. Make changes in T, and write into file using xlswrite or writetable.
  2 Comments
Sam Smith
Sam Smith on 8 Nov 2018
Edited: Sam Smith on 8 Nov 2018
Thank you. This is a way of doing it, but is there a way of doing it if I want to do the fopen-fread-char routine? xlsread changes the time to a number which I don't want.
KSSV
KSSV on 9 Nov 2018
You can use xlsread s below:
[num,txt,raw] = xlsread(myfile) ;
Now raw, will have all the data of excel file. No change in the data.

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