How to extract specific data from data files

There are multiple data files and I attached two as examples. For each of the data file, there are two data blocks. I want to extract the line corresponding to F=1.0000 in each data block, and combine the two lines into one. Then create a new file which includes the extracted data for all the data files.

For file "test1", the two lines corresponding to F=1.0000 are

• 1.0000 0.98581 -23.906 5.74804 164.322
• 1.0000 0.0674 0.84738 9.741 0.2434

The extracted data would be

• 1.0000 0.98581 -23.906 5.74804 164.322 0.0674 0.84738 9.741 0.2434

Similarly, the extracted data for file "test2" would be

• 1.0000 0.98373 -23.184 5.52288 164.574 0.0690 0.84402 12.860 0.2598

The new file I want to obtain will include the extracted data from "test1" and "test2"

• 1.0000 0.98581 -23.906 5.74804 164.322 0.0674 0.84738 9.741 0.2434
• 1.0000 0.98373 -23.184 5.52288 164.574 0.0690 0.84402 12.860 0.2598

What's a good way to realize this? Thank you.

Answer 1

[Bob Thompson]

I'm fairly certain there is a better way of doing this, but I personally would scan through each document with a for loop, and then use fgetl to extract the specific lines.

for nf = 1:length(files); % Loop through all files
 count = 0; % Reset line counter
 line = 1; % Reset line value
 a = 1;
 file = fopen(files(nf)); % Open new file
 while line ~= -1; % Run to end of file
  line = fgetl(file); % Read next line
  if length(line)<5; % Ignore small lines
  elseif strcmp(line(1:6)),'1.0000')==1; % Look for lines beginning with desire value
   datahold(a,:) = num2str(line); % You may have issues with this line converting correctly, but this should give
                                  % the concept of what you want to accomplish
   a = a+1; % Add new line to array for new data to recover
  end % Line value check
  count = count+1; % Advance line count
 end % while loop
 extracted(nf,:) = [datahold(1,:) datahold(2,2:end)]; % Only accounts for two lines extracted, transforms to one line
end % File loop

It's far from perfect, but it should get you started.

[Dq Hu]

Thank you very much Bob. It's good enough for me to start with.