txt file to matlab matrix form

. I have another question.If a text file (attached)in which corresponding to each row all the column values are given e.g.

ROW 1 NODE 1 DEG. OF. FR. = ROTZ

    1 0.13513535E+09    2 0.00000000E+00    3 0.91507762E+08    4-0.59130175E+08
    5 0.00000000E+00    6 0.00000000E+00    7 0.00000000E+00    8-0.36603105E+09
    9 0.00000000E+00   10 0.00000000E+00   11 0.00000000E+00   12 0.10701035E+09
   13 0.00000000E+00   14 0.00000000E+00   15 0.00000000E+00   16 0.00000000E+00
   17 0.00000000E+00   18 0.00000000E+00
   ROW   2   NODE     2     DEG. OF. FR. =  UX  
    1 0.00000000E+00    2 0.35000101E+10    3 0.00000000E+00    4 0.00000000E+00
    5 0.25000125E+09    6 0.00000000E+00    7-0.20000063E+10    8-0.33333439E+06
    9 0.00000000E+00   10 0.00000000E+00   11 0.00000000E+00   12 0.00000000E+00
   13-0.20000063E+10   14 0.33333439E+06   15 0.00000000E+00   16 0.00000000E+00
   17 0.00000000E+00   18 0.00000000E+00
and so on upto 18 rows ( *Please see the attached file for clarity* ). What modification I need to do in my code to get a 18x18 matrix.

Again thank you for your quick responses. It will help me to progress further in my work

Answer 1

[Stephen23]

Try this. Firstly read the file into a string (note that I removed the space at the end of the filename):

str = fileread('STIFFNESS MATRIX.txt');

Then extract the data from the block headers, including the row numbers:

[tok,idx] = regexp(str, 'ROW\s+(\d+)\s+NODE\s+(\d+)\s+[^\n=]+=\s+(\w+)', 'tokens', 'end');
tok = vertcat(tok{:});
idx = [1+idx,numel(str)];

Extract the data from the blocks:

fun = @(b,e)reshape(sscanf(str(b:e),'%f'),2,[]).';
mat = arrayfun(fun, idx(1:end-1), idx(2:end), 'UniformOutput',false);

Convert the data from string into numeric:

fun = @(r,v)[sscanf(r,'%i')*ones(size(v,1),1),v];
mat = cellfun(fun, tok(:,1), mat(:), 'UniformOutput',false);
mat = vertcat(mat{:});

And finally transfer the numeric data into one single numeric array, by using the row and column indices to allocate the data:

out = zeros(size(tok,1));
ind = sub2ind(size(out),mat(:,1),mat(:,2));
out(ind) = mat(:,3)

This gives one matrix containing the complete data:

>> out
out =
 1.0e+09 *
Columns 1 through 14
  0.1351  0  0.0915   -0.0591  0  0  0   -0.3660  0  0  0 ...
Columns 15 through 18
       0         0         0         0
       0         0         0         0
...
       0         0         0         0
       0         0         0         0
  1.4636   -0.0000         0         0
 -0.0000    0.0138    0.0001         0
       0    0.0001    0.5012         0
       0         0         0    0.5180

[Stephen23]

This question and answer is continued here:

http://www.mathworks.com/matlabcentral/answers/212882-importing-data-from-a-text-file-in-matrix-form