Reading data row by row into matlab.

I need to read a text file, row by row, into different variables for the first 5 rows. Afterwards an N x M matrix needs to be read in. Is there a simple way to do this? I've tried to use textrfead, fopen, etc, but can't figure out how to get just the numbers I need.

this would be a sample file:

8

10

12 15 12 18 17 19 14 16

200 155 487 632 526 321 845 80

52 41 78 62 32 45 67 85 29 10 15

followed by a matrix of size 8 x10 (the matrix will always be size of the first two inputs)

Sorry, I uploaded two sample files. I know how to read in everything but the matrix at the end. That's what I need help retrieving from the files.

[Kevin Chng]

It is a bit confusing about

for the first 5 rows. After words an N x M matrix needs to be read in.

I guess you are only wanted to read certain line in your text file.

https://www.mathworks.com/matlabcentral/answers/306876-how-do-i-read-only-a-specific-line-while-reading-a-text-file-in-matlab

If you could upload your text file, and let us know which line you want to read, i can try to write the code for you here.

[Jorge Guzman]

I uploaded sample files. I can read everything except for line 6 onward as a matrix. I need to be able to read in different sized matrices.

Answer 1

[Stephen23]

Why not just use dlmread ?:

>> M = dlmread('test.txt','',2,0)
M =
    12    15    12    18    17    19    14    16     0     0     0
   200   155   487   632   526   321   845    80     0     0     0
    52    41    78    62    32    45    67    85    29    10    15

I had to create my own test file (attached) based on your description because you did not provide one. If you upload a sample file then it makes it easier for us to help you, and faster for you to get the results that you want.

[Jorge Guzman]

Thank you, this works i just needed to offset by 5. since the matrix is found on the 6th line and onward!

Answer 2

[Are Mjaavatten]

I often find it useful to read the file into a cell array of strings using textscan. Then I can easily experiment with how to best parse each line. In your case, this resulted in:

fid = fopen(filename);
lines = textscan(fid,'%s','delimiter','\n');
fclose(fid);
lines = lines{1};
n = sscanf(lines{1},'%d');
m = sscanf(lines{2},'%d');
% parse lines 3-5
M = zeros(n,m);
for i = 1:n
  M(i,:) = sscanf(lines{5+i},'%f')';
  % Alternatively:
  % M(i,:) = str2num(lines{5+i});
end

[Yasir Iqbal]

Brilliant