how to extract part of the information?

Question

Chathu 2015-1-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/171290-how-to-extract-part-of-the-information

评论： Chathu 2015-1-23

采纳的回答： Guillaume

在 MATLAB Online 中打开

This is what i have. (note: originally i have 7 columns but i have only shown just 2 columns for convenience)

'No.' 'Time'

    '1'       '0.000000000' 
    '2'       '0.100209000' 
    '3'       '0.199458000' 
    '4'       '0.299589000' 
    '5'       '0.399856000' 
    '6'       '0.499050000' 
    '7'       '0.599287000' 
    '8'       '0.698449000' 
    '9'       '0.798677000' 
    '10'      '0.898885000' 
      '
    '1000'    '99.00000000'

Here is the code i use to extract

 fid  = fopen('eT1.txt', 'r');
data = textscan(fid, '%d%f%s%s%s%d%s', 'MultipleDelimsAsOne',true, 'HeaderLines',1);
fclose(fid);

But what i want only 1000 values extracted. In that case i need all the 7 columns but till No==1000. how to do that?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Guillaume 2015-1-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/171290-how-to-extract-part-of-the-information#answer_165723

在 MATLAB Online 中打开

Assuming you only want 1000 rows and not just 1000 values (which is not a multiple of 7):

data = textscan(fid, '%d%f%s%s%s%d%s', 1000, 'MultipleDelimsAsOne',true, 'HeaderLines',1);

It's all there in the documentation of textscan (parameter N)

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Chathu 2015-1-23

@ Guillaume- actually i even typed the very same thing as your code except i placed the value '1000' after true.That's why it didn't work.

Your code works beautifully. Thanks alot.

请先登录，再进行评论。

Answer 2

Azzi Abdelmalek 2015-1-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/171290-how-to-extract-part-of-the-information#answer_165690

编辑：Azzi Abdelmalek 2015-1-23

在 MATLAB Online 中打开

n=1000
data=cell(n,1);
fid  = fopen('file.txt', 'r');
fgetl(fid);
for k=1:n
 data{k} = fgetl(fid);
end
fclose(fid);
celldisp(data)

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Chathu 2015-1-23

在 MATLAB Online 中打开

@ Azzi- thank you for your response.

Can you kindly tell me, what does '1' refers in the below line:

data=cell(n,1);

Here is what i obtain:

ans{1} =

      1 0.000000000    192.168.20.30         192.168.20.2          UDP      60     03ff00000166

but i want to obtain everything in separate columns(as shown below) with their respective headers. How to obtain that?

 No         Time
'1'       '0.000000000' 
'2'       '0.100209000'

请先登录，再进行评论。

Answer 3

Image Analyst 2015-1-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/171290-how-to-extract-part-of-the-information#answer_165705

在 MATLAB Online 中打开

You forgot to attach your file. Are the single quotes actually in your file or not? Whynot just use a table:

t = readtable(filename);

3 个评论
显示 1更早的评论隐藏 1更早的评论

Image Analyst 2015-1-23

readtable() takes alphanumeric values. It should be the easiest way, though it requires R2013b or later. You could speed things up (the back and forth question asking) if you would just attach the file, at least just a few lines of it.

Chathu 2015-1-23