How to extract every repeated sequence line from text file using MATLAB

Time(sec) 20.30
Type 1
Svid  slew  power used 
12.    0.33 -36dbm y
10     .38. -40dbm N
08.    0.40 -30dbm Y
Time(sec) 20.40
Type 2
Svid  slew  power used 
12.   0.46. -38dbm Y
06.   0.50. -32dbm Y
02.   0.42. -30dbm N
sequence repeats....

How to pull out all Type-1 SVID 12 row which is repeating (say after 10 line). How can I save it to new file so that I can manipulate for further processing. Any help is highly appreciated! POKA

[per isakson]

I didn't understand your last question, which was very similar to this one. And I don't understand this question.

What exactly do you want to write to the new file?

[POKA]

My last question which I posted yesterday night was not clear because of my editing issue. So today same question I have repeated again

[POKA]

Hi , As you can see there are two type of data under two heading Type 1 and Type 2 having different time instance . These are satellite data .At one time I want to extract all data row of psricular sv id corresponding to time . this sv is repeated after particular sequence. So my intention is to pull out say all Sv id 12 of type 1 data .

[Stephen23]

See also the preceding question:

https://www.mathworks.com/matlabcentral/answers/351296-extract-every-2-6-10-and-3-7-11-line-irrespective-of-data-type-from-text-file-using-matlab

[POKA]

 I got the solution using
 KSSV initial reading 
 file technique
 and then pulling data
 using indexwise

Answer 1

[KSSV]

You can get the indices of your string Type 1 and Svid1 using the below code:

fid = fopen('data.txt') ;

S = textscan(fid,'%s','delimiter','\n') ;
S = S{1} ;
fclose(fid) ;
%%gEt string Type 1
idx1 = find(not(cellfun('isempty', strfind(S, 'Type 1'))));   % lower then 2016b
% idx1 = contains(S,'Type 1') ;
% idx1 = find(idx==1) ;
% GEt string Svid
idx2 = find(not(cellfun('isempty', strfind(S, 'Svid'))));

Once you have indices you can extract what you want..

[POKA]

Okay thanks for response . I will check it . what is idx==1 doing here . did not get this part

[POKA]

 Hello,
 I m getting undefined function cell.

[KSSV]

Check is S is your complete text data or not......which line number error comes? What version you are using?

[POKA]

I got it ! S=S{1}; X=S(2:4:end,:); Where x is my sv id staring location and will search after every 4th interval till end.thanks it worked.I did not know textscan is so powerful !

[KSSV]

Thanks is accepting the answer :)

[Jan]

textscan is as powerful as the cheap:

S = strsplit(fileread(FileName), '\n');

[per isakson]

@Jan Simon, with strings that has CRLF as newline character, strsplit and textscan use the delimiter \n differently

>> strsplit( sprintf( '%s\r\n%s', 'A','B' ), '\n' )
ans = 
    'A…'    'B'
>> double(ans{1})
ans =
    65    13
>> cac = textscan( sprintf( '%s\r\n%s', 'A','B' ), '%s%s', 'Delimiter','\n' )
cac = 
    {1x1 cell}    {1x1 cell}
>> cac{1}
ans = 
    'A'

[Walter Roberson]

By default, \r is 'whitespace' for textscan() but strsplit() treats it as just another character.

strsplit() calls regexp(). You can go more directly:

 S = sprintf( '%s\r\n%s', 'A','B' );
 cac = regexp( S, '\r?\n', 'split');

[per isakson]

It's more to it

>> cac = textscan( sprintf( '%s\r\n%s', 'A','B' ), '%s%s', ...
'Delimiter','\n', 'Whitespace','' )
cac = 
    {1x1 cell}    {1x1 cell}
>> double(cac{1}{:})
ans =
    65
>>