How to read .raw files of unknown number of rows and 9 columns

I have multiple .raw files of format:

-1.1972430e+00   1.9116530e+00  -1.6151377e+01  -1.6761160e+00   1.3295020e+00  -1.5595563e+01  -1.3040950e+00   1.6830060e+00  -1.5456139e+01
-1.1972430e+00   1.9116530e+00  -1.6151377e+01  -1.8009150e+00   1.4511150e+00  -1.6474810e+01  -1.6761160e+00   1.3295020e+00  -1.5595563e+01
-1.1559240e+00   2.0341980e+00  -1.6435989e+01  -1.8009150e+00   1.4511150e+00  -1.6474810e+01  -1.1972430e+00   1.9116530e+00  -1.6151377e+01
.
.
.
 2.2807209e+00   2.8720999e-02  -1.0023850e+00   2.3006320e+00   2.7641000e-02  -7.0393997e-01   2.3620090e+00   3.5114399e-01  -8.2908899e-01
 2.3591161e+00  -3.3455700e-01  -8.3278698e-01   2.3006320e+00   2.7641000e-02  -7.0393997e-01   2.2807209e+00   2.8720999e-02  -1.0023850e+00
 2.2807209e+00   2.8720999e-02  -1.0023850e+00   2.3961921e+00  -3.2150501e-01  -1.1897759e+00   2.3591161e+00  -3.3455700e-01  -8.3278698e-01

Each file has 9 columns and unknown number of rows.

Each row (consisting of 9 numbers) are just the x,y,z coordinates of the three vertices of a triangle.

I would like to iteratively read in each row and place it in a vector for further manipulations.

I have attempted using fread() to do this. I have searched the internet and the questions on this website, but all of them seem to know the dimensions of their .raw file (row AND column).

Thanks!

Answer 1

[dpb]

fid=fopen(...
while ~feof(fid)
  v=cell2mat(textscan(fid,'%f',9,'collectoutput',1));
  % do whatever with _v_ here
  ...
end
fid=fclose(fid);

Alternatively, unless the files are huge, it'll be faster to read the array and process it from memory rather than reading the file record-by-record. (Plus, you may well be able to vectorize the "whatever" and avoid any looping altogether, almost always agoodthing (tm) in Matlab to strive for...

In that case,

fid=fopen(...
a=cell2mat(textscan(fid,'','collectoutput',1));
fid=fclose(fid);
% process the array here...

NB: Two things--first, note that wrapped the textscan call inside cell2mat to return a double array instead of a cell array; when the data are all numeric is much simpler addressing and less overhead. Second, in the second case the use of the empty format string is a flag to textscan that it will return the array in the shape found in the file automagically--you don't need to know either number of records nor items per record as long as it is a regular array.

[trent]

Thank you for such a clear answer. The file is small enough to process from memory, so I will use the second method.

Thanks!