readmatrix ignores the first line of the data file

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I'm trying to read a text filw with over 226,600 rows with readmatrix (sample is over 5MB so I couldn't attach it here). The first line is numeric but readtable ignores the first line. Following is the line I'm using is follows, and I do require the structure (with NaN) that this provides.
data = readmatrix('sample.txt', 'Delimiter',' ','ConsecutiveDelimitersRule', 'join');
I found a similar thread where table2array was suggested, but I get the "Input argument must be a table." error. How can I rectify this?
** edit: A trimmed sample file is uploaded.
  2 Commenti
Stephen23
Stephen23 il 9 Mar 2023
"How can I rectify this?"
Did you try specifying the first data line, or the number of header lines, or any other related options?
Please trim the file down a bit and upload it here.
Jake
Jake il 9 Mar 2023
Hi @Stephen23, I uploaded a trimmed data file.
The solution provided by @Sarvesh Kale seems to work for the time being, but I'd rather have a method where I don't have to add a line manually, since soon I will be dealing with multiple files similar to this.

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Risposta accettata

Stephen23
Stephen23 il 9 Mar 2023
Modificato: Stephen23 il 9 Mar 2023
You can specify the RANGE as the starting row:
M = readmatrix('sample.txt', 'ConsecutiveDelimitersRule','join', 'Range',1)
M = 11020×15
-1.0000 1.0000 1.0000 0.0303 0 -0.0446 0 0.1337 0 -0.0016 0 0.0647 0 0.0461 0 0.0027 0 0.0012 0 0 0 0 0 -0.0027 0 -0.0012 0 NaN NaN NaN -0.0054 0 -0.0025 0 -0.0082 0 -0.0037 0 -0.0109 0 -0.0049 0 NaN NaN NaN -0.0136 0 -0.0061 0 -0.0164 0 -0.0072 0 -0.0191 0 -0.0083 0 NaN NaN NaN -0.0219 0 -0.0094 0 -0.0246 0 -0.0104 0 -0.0274 0 -0.0114 0 NaN NaN NaN -1.0000 1.0000 2.0000 0.0318 0 -0.0505 0 0.1375 0 -0.0017 0 0.0679 0 0.0521 0 0.0030 0 0.0015 0 0 0 0 0 -0.0030 0 -0.0015 0 NaN NaN NaN -0.0061 0 -0.0030 0 -0.0092 0 -0.0045 0 -0.0122 0 -0.0060 0 NaN NaN NaN -0.0153 0 -0.0075 0 -0.0184 0 -0.0089 0 -0.0215 0 -0.0103 0 NaN NaN NaN -0.0246 0 -0.0116 0 -0.0277 0 -0.0129 0 -0.0308 0 -0.0141 0 NaN NaN NaN
I note that the data are arranged in blocks which span multiple lines. Note that if all files have a fixed, known format then you might consider using FSCANF to reads those blocks of data, giving one row per block, e.g.:
nmc = 15+12*4;
fmt = repmat('%f',1,nmc);
fid = fopen('sample.txt','rt');
mat = fscanf(fid,fmt,[nmc,Inf]).';
fclose(fid);
display(mat)
mat = 2204×63
-1.0000 1.0000 1.0000 0.0303 0 -0.0446 0 0.1337 0 -0.0016 0 0.0647 0 0.0461 0 0.0027 0 0.0012 0 0 0 0 0 -0.0027 0 -0.0012 0 -0.0054 0 -0.0025 -1.0000 1.0000 2.0000 0.0318 0 -0.0505 0 0.1375 0 -0.0017 0 0.0679 0 0.0521 0 0.0030 0 0.0015 0 0 0 0 0 -0.0030 0 -0.0015 0 -0.0061 0 -0.0030 -1.0000 1.0000 3.0000 0.0305 0 -0.0402 0 0.1327 0 -0.0013 0 0.0649 0 0.0418 0 0.0024 0 0.0012 0 0 0 0 0 -0.0024 0 -0.0012 0 -0.0048 0 -0.0024 -1.0000 1.0000 4.0000 0.0301 0 -0.0314 0 0.1318 0 -0.0010 0 0.0634 0 0.0327 0 0.0019 0 0.0009 0 0 0 0 0 -0.0019 0 -0.0009 0 -0.0038 0 -0.0018 -1.0000 1.0000 5.0000 0.0308 0 -0.0316 0 0.1329 0 -0.0009 0 0.0646 0 0.0330 0 0.0019 0 0.0010 0 0 0 0 0 -0.0019 0 -0.0010 0 -0.0037 0 -0.0020 -1.0000 1.0000 6.0000 0.0316 0 -0.0416 0 0.1357 0 -0.0012 0 0.0672 0 0.0433 0 0.0025 0 0.0014 0 0 0 0 0 -0.0025 0 -0.0014 0 -0.0050 0 -0.0028 -1.0000 1.0000 7.0000 0.0326 0 -0.0533 0 0.1392 0 -0.0017 0 0.0700 0 0.0550 0 0.0032 0 0.0017 0 0 0 0 0 -0.0032 0 -0.0017 0 -0.0064 0 -0.0035 -1.0000 1.0000 8.0000 0.0324 0 -0.0444 0 0.1379 0 -0.0012 0 0.0692 0 0.0461 0 0.0026 0 0.0016 0 0 0 0 0 -0.0026 0 -0.0016 0 -0.0053 0 -0.0031 -1.0000 1.0000 9.0000 0.0333 0 -0.0559 0 0.1413 0 -0.0016 0 0.0722 0 0.0575 0 0.0033 0 0.0020 0 0 0 0 0 -0.0033 0 -0.0020 0 -0.0067 0 -0.0039 -1.0000 1.0000 10.0000 0.0349 0 -0.0650 0 0.1443 0 -0.0021 0 0.0741 0 0.0663 0 0.0039 0 0.0022 0 0 0 0 0 -0.0039 0 -0.0022 0 -0.0077 0 -0.0044

Più risposte (1)

Sarvesh Kale
Sarvesh Kale il 9 Mar 2023
Hi Jake,
You can open the text file in notepad and insert some text that best describes your data on the first line, from second line your data will start and I guess this should resolve your problem
Thank you
  1 Commento
Jake
Jake il 9 Mar 2023
Hi, @Sarvesh Kale, this seems to work but it would be quite difficult to do this manually, since I will have to deal with several files soon. Thank you!

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