How to ignore the headerline

Hi all.

I have 173 txt files look like:

* number etc......

20 44.581273 131.198920 45.413450 6/9/2018 8.301089 700 800 20

20 37.821101 149.679660 52.175950 6/9/2018 9.231156 600 600 20

20 34.834385 166.779660 55.163450 6/9/2018 9.937562 700 700 20

20 35.097478 195.417160 54.900950 6/9/2018 11.030783 800 800 20

I want to take these data and create a matrix with 11 columns ignoring the headerline.

I did it:

 format1='%f %f %f %f %f/%f/%f %f %f %f %f'; 
 files=dir('*.txt');
 N=length(files);
for k = 1:N 
  fid = fopen(files(k).name,'r');
  
  A=textscan(fid,format1,'Commentstyle','*');
  B{k,1}=cell2mat(A);
  
  %clear A 
  
  fclose(fid);
end

but I take empty matrix B.

Any ideas??

Answer 1

[Guillaume]

Your file format looks like something that readtable should have no problem figuring out, so try:

files = dir('*.txt');
filesdata = cell(size(files));  %preallocate the cell array that receive the file content (your badly named B)
for fileidx = 1:numel(files)
    filesdata{fileidx} = readtable(files(fileidx).name);
end

If readtable needs some help, then either:

    filesdata{fileidx} = readtable(files(fileidx).name, 'ReadVariableNames', false);

or

    filesdata{fileidx} = readtable(files(fileidx).name, 'ReadVariableNames', false, 'HeaderLines', 1);  

should get it to work.

[Thar]

the final data from this is one only column:

'38 63.661438 175.006616 26.343800 1/1/2017 10.204592 400 500 38'

'37 63.688200 185.397530 26.343800 1/1/2017 10.879201 500 500 37'

'36 65.483929 197.417800 24.520883 1/1/2017 11.676208 600 700 36'

'35 68.115081 206.296371 21.890229 1/1/2017 12.297357 600 700 35'

'33 72.443509 216.042800 17.571073 1/1/2017 13.032790 900 1000 33'

'26 78.063922 225.206262 11.944762 1/1/2017 13.793572 1600 1700 26'

I want to have these in different columns.

[Guillaume]

Please attach an example file. As said, readtable should have no problem identifying the format of your file so if it doesn't that's because there's something peculiar about it. The only way to know for sure is with an actual file.

[Guillaume]

readtable (R2018b) has no problem identifying the columns of your text file:

>> t = readtable('001.txt')
Warning: The DATETIME data was created using format 'MM/dd/uuuu' but also matched 'dd/MM/uuuu'.
To avoid ambiguity, use a format character vector. e.g. '%{MM/dd/uuuu}D' 
> In table/readTextFile>textscanReadData (line 557)
  In table/readTextFile (line 228)
  In table.readFromFile (line 41)
  In readtable (line 216) 
t =
  10×9 table
    Var1     Var2      Var3      Var4        Var5        Var6     Var7    Var8    Var9
    ____    ______    ______    ______    __________    ______    ____    ____    ____
     27     76.621    136.77    13.367    02/01/2017    7.4455    1400    1500     27 
     31     70.869    146.91    19.122    02/01/2017    8.2649     900    1000     31 
     33     66.703    157.68    23.291    02/01/2017    9.0521     800     900     33 
     36     64.248    168.63    25.743    02/01/2017    9.7954     600     700     36 
     35     63.414     179.4    26.594    02/01/2017    10.498     600     700     35 
     36     64.096     190.3    25.906    02/01/2017    11.207     600     700     36 
     35     66.189    200.56    23.805    02/01/2017    11.898     600     700     35 
     33     69.704    210.54    20.302    02/01/2017    12.614     800     900     33 
     27     74.781    220.35    15.223    02/01/2017    13.385    1500    1700     22 
      2      82.11    230.67    7.9063    02/01/2017    14.292    5000    5100      2 

You get a table with 10 rows, and 9 variables (columns).

edit: However, I've just noticed that it missed the first row of number. Easily fixed:

>> t = readtable('001.txt', 'HeaderLines', 1, 'ReadVariableNames', false)
Warning: The DATETIME data was created using format 'MM/dd/uuuu' but also matched 'dd/MM/uuuu'.
To avoid ambiguity, use a format character vector. e.g. '%{MM/dd/uuuu}D' 
> In table/readTextFile>textscanReadData (line 557)
  In table/readTextFile (line 228)
  In table.readFromFile (line 41)
  In readtable (line 216) 
t =
  11×9 table
    Var1     Var2      Var3      Var4        Var5        Var6     Var7    Var8    Var9
    ____    ______    ______    ______    __________    ______    ____    ____    ____
      1     84.167    126.79    5.8438    02/01/2017    6.5485    6000    6000      0 
     27     76.621    136.77    13.367    02/01/2017    7.4455    1400    1500     27 
     31     70.869    146.91    19.122    02/01/2017    8.2649     900    1000     31 
     33     66.703    157.68    23.291    02/01/2017    9.0521     800     900     33 
     36     64.248    168.63    25.743    02/01/2017    9.7954     600     700     36 
     35     63.414     179.4    26.594    02/01/2017    10.498     600     700     35 
     36     64.096     190.3    25.906    02/01/2017    11.207     600     700     36 
     35     66.189    200.56    23.805    02/01/2017    11.898     600     700     35 
     33     69.704    210.54    20.302    02/01/2017    12.614     800     900     33 
     27     74.781    220.35    15.223    02/01/2017    13.385    1500    1700     22 
      2      82.11    230.67    7.9063    02/01/2017    14.292    5000    5100      2