Extracting data from text file

2022 2 7
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I have a text file (attached). I am trying to extract a specific part (Nodes part) starting by reading the header (nodal.coordinates) then extract the following four columns (node name, x, y and z). I am trying textscan ad cell2mat functions but I got an empty matrix. Many thanks in advance.

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Stephen23
Stephen23 2022-2-7
编辑：Stephen23 2022-2-7
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Ran in:
Method one: TEXTSCAN:
fmt = '%s%f%f%f';
opt = {'MultipleDelimsAsOne',true, 'CollectOutput',true, 'HeaderLines',1};
fid = fopen('sampleQ.txt','rt');
while ~feof(fid) && ~strcmp(fgetl(fid),'nodal.coordinates')
end
out = textscan(fid,fmt,opt{:});
fclose(fid);
out{:}
ans = 8×1 cell array
{'n111' } {'n111-y1'} {'n111-y2'} {'n111-y3'} {'n121' } {'n121-x1'} {'n121-x2'} {'#' }
ans = 7×3
0 0 0 0 450 0 0 1500 0 0 2550 0 0 3000 0 600 3000 0 2000 3000 0
Method two: REGEXP:
str = fileread('sampleQ.txt');
str = regexp(str,'(?<=nodal\.coordinates\s+)[^#]+','match','once');
tkn = regexp(str,'^\s*(\S+)\s+(\d\S+)\s+(\d\S+)\s+(\d\S+)','tokens','lineanchors');
tkn = vertcat(tkn{:})
tkn = 7×4 cell array
{'n111' } {'0.' } {'0.' } {'0.'} {'n111-y1'} {'0.' } {'450.' } {'0.'} {'n111-y2'} {'0.' } {'1500.'} {'0.'} {'n111-y3'} {'0.' } {'2550.'} {'0.'} {'n121' } {'0.' } {'3000.'} {'0.'} {'n121-x1'} {'600.' } {'3000.'} {'0.'} {'n121-x2'} {'2000.'} {'3000.'} {'0.'}
mat = str2double(tkn(:,2:end))
mat = 7×3
0 0 0 0 450 0 0 1500 0 0 2550 0 0 3000 0 600 3000 0 2000 3000 0

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