필터 지우기
필터 지우기

how to let 'textscan' stop when read an empty line

조회 수: 8 (최근 30일)
Ken
Ken 2012년 7월 24일
I have double quoted csv file:
"header1"
(descriptions)
"A","B","3","A","B","3"
"C","B","3","T","B","2"
"D","B","3","A","H","3"
"E","B","3","A","B","6"
"F","B","3","Z","J","3"
(empty line here)
"header2"
(descriptions)
"A","B","3","A","B","3"
"C","B","5","A","B","3"
"D","B","4","A","H","3"
"E","B","3","A","L","1"
"F","B","2","A","I","3"
I tried to use:
fid=fopen('..\data.csv', 'r')
fgetl(fid)
fgetl(fid)
inputtext = textscan(fid, '%q%q%q%q%q%q', ...
'delimiter', ',');
but it reads everything until hits the end of the data file (including header2). How to read data above the empty line? Thanks!!

채택된 답변

Ken
Ken 2012년 7월 24일
편집: Ken 2012년 7월 24일
instead of reading the whole block of data using textscan, I tried to read it into a cell line by line. Textscan will stop when hits the empty line.
Code:
while (~feof(fid_t))
temp1 = fgetl(fid_t);
if isempty(temp1)
break;
end
inputtext=textscan(temp1, formatstring,...
'delimiter',',')
temp_out=[inputtext{:}];
Data(end+1,:)=temp_out;
end
and it works finally. It is still not an effective way, but it works. any suggestion?

추가 답변 (1개)

Walter Roberson
Walter Roberson 2012년 7월 24일
textscan() is not designed for this.
You can remove newline from the Whitespace list, but to compensate you have to explicitly match newline in your textscan() format at the point you expect newline to be.
  댓글 수: 2
Ken
Ken 2012년 7월 24일
편집: Ken 2012년 7월 24일
Walter. Actually I got the idea from
The code there (textscan) could read a block of data into a matrix. Textscan stopped reading data-line when there was an empty line. I really don't know the trick, or maybe they used other commands? I am trying to do the same thing but it failed :(. Textscan reads everything.
I will try your advice for removing newlines from 'empty line', but sounds not an effective way ...
Walter Roberson
Walter Roberson 2012년 7월 24일
That particular demo is reading blocks of floating point numbers rather than strings. Different stopping conditions internally, unfortunately.

댓글을 달려면 로그인하십시오.

카테고리

Help CenterFile Exchange에서 Large Files and Big Data에 대해 자세히 알아보기

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by