MATLAB: Data extraction with undefined file length

sscanf

I have a large data file and I want to extract specific data from this file. However, I want to program the system in such a way that I can input the same sort of data file into the program and it will still give the same outcome. So for example, there is a string called

tline =' : W A V E P E R I O D = 3.6000E+01 : ';

within the data file. This string occurs on different locations for different data files. What I want to extract from the data file is 3.6000E+01. What I have got so far (but does not work) is:

A = sscanf(tline,' : W A V E P E R I O D = %1.4e : ');

Regards, Mark.

Best Answer

Try this

str = fileread( 'lorem.txt' );
cac = regexp( str, '(?<=W A V E P E R I O D =)\s*[\d\.\E\+\-]+', 'match','once' )

it outputs

cac =
 3.6000E+01

where lorem.txt is attached

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[U, d] = eig(k, m, 'vector');
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MATLAB: Extracting data from file.

Hello,

Here the code.

I think it is very complicated works with your data.

But I have write this code.

clear; clc;
fid = fopen('Data01.txt'); 
tline = fgetl(fid);
x = 1;
while ischar(tline) 
    data01{x} = tline; 
    tline = fgetl(fid);
    x = x + 1;
end
fclose(fid);
id1 = 1;    id2 = 1;
querystr1 = 'surface(21<12<13)'; %don't use space

querystr2 = 'cosinebin:-8.72000E-02to-3.66000E-02'; %don't use space
for x = 1 : length(data01)
    tmpdata = regexprep(data01{x},' ','');
    if strcmp(tmpdata,querystr1) == 1
        linestr1(id1) = x;    id1 = id1 + 1;
    end
    if strcmp(tmpdata,querystr2) == 1
        linestr2(id2) = x;    id2 = id2 + 1;
    end
end
for x = 1 : length(linestr1)
    for y = 1 : length(linestr2)
        diff = abs(linestr1(x) - linestr2(y));  
        if diff == 1
            lowintv = linestr2(y) + 2;
        end
    end
end
idk = 1;
idl = lowintv;
while ~any(findstr(data01{idl},'total'));       
    data02{idk} = textscan(data01{idl},'%f %f %f');  
    idk = idk + 1;    
    idl = idl + 1;    
end

Now you can get your data stored in variable 'data02'.

Note that you can change the variable 'querystr1' and 'querystr2' with two headers that you want to search.

But, you maynot insert any space in variable 'querystr1' and 'querystr2'.

Try to run it.

Best Answer

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MATLAB: Get in Order respond when using “eig” command

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