Load in multiple text files and store data in a matrix

I have 28 text files, of this pattern:

 out.200.data
 out.225.data

up to

 out.900.data

How can I populate the 3rd row into a matrix? Note that there are 3 columns in the 3rd row. I also have a path to my files, but for purposes here, let's just say the path is just C:/Path

Is there a way to create a single matrix with these values?

Row 1 of the matrix is the 3rd row of out.200.data
Row 2 of the matrix is the 3rd row of out.225.data

etc?

[TAB]

What is format of your data in text file?

[Benjamin Cowen]

2 header rows

3rd row is 3 numbers, separated by spaces

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

for information on looping over files.

For any one file, I suggest something like

   filename = fullfile(projectdirectory, dinfo(K).name);
   fid = fopen(filename, 'rt');
   row3(K,:) = cell2mat( textscan(fid, '%f%f%f', 1, 'headerlines', 2, 'collectoutput', true) );
   fclose(fid)

[Benjamin Cowen]

I have no idea how to convert that to my problem.

[Walter Roberson]

projectdirectory = 'C:/Path';
dinfo = dir( fullfile(projectdir, 'out.*.data') );
N = length(dinfo);
row3 = zeros(N, 3);

for K = 1 : N
  filename = fullfile(projectdirectory, dinfo(K).name);
  fid = fopen(filename, 'rt');
  row3(K,:) = cell2mat( textscan(fid, '%f%f%f', 1, 'headerlines', 2, 'collectoutput', true) );
  fclose(fid);
end

[Benjamin Cowen]

@Walter Roberson Thanks for this, it worked. If I only have 1 headerline, I want to extract the 51st row, and there are only 2 columns as opposed to 3, why does this not work:

clear
clear all
clc

projectdirectory = 'C:/Path/';
dinfo = dir( fullfile(projectdirectory, 'msd.*.data') );
N = length(dinfo);
row51 = zeros(N, 2);
for K = 1 : N
  filename = fullfile(projectdirectory, dinfo(K).name);
  fid = fopen(filename, 'rt');
  row51(K,:) = cell2mat( textscan(fid, '%f%f', 50, 'headerlines', 1, 'collectoutput', true) );
  fclose(fid);
end

[Walter Roberson]

clear
%let us refrain from blowing up the bridge we are standing on, like Wile E. Coyote
%<<https://cdn-images-1.medium.com/max/1338/1*8oK7yw-tYvP14l_Ya3Nvcg.png>>
%clear all
clc

Row_to_extract = 51;
projectdirectory = 'C:/Path/';
dinfo = dir( fullfile(projectdirectory, 'msd.*.data') );
N = length(dinfo);
row = zeros(N, 2);
for K = 1 : N
  filename = fullfile(projectdirectory, dinfo(K).name);
  fid = fopen(filename, 'rt');
  row(K,:) = cell2mat( textscan(fid, '%f%f', 1, 'headerlines', Row_to_extract - 1, 'collectoutput', true) );
  fclose(fid);
end