Readtable gives unusual results reading data from a text file.

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I'm trying to read a lot of text files using readtable. All the files have 7 columns of data, although the last column is usually blank.
Readtable normally gives this:
39×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7
____ ____ ____ ____ ____ ____ __________
2009 10 6 3 33 29 {0×0 char}
2009 10 6 3 36 12.3 {0×0 char}
2009 10 6 3 36 53.3 {0×0 char}
2009 10 6 3 37 6.5 {0×0 char}
...
But one text file gives a very different result:
7×1 table
x20111118015544_7RF
_________________________
{'2011 11 18 01 33 43.7'}
{'2011 11 18 01 33 51.2'}
{'2011 11 18 01 33 60.0'}
{'2011 11 18 01 35 32.3'}
{'2011 11 18 01 36 03.9'}
{'2011 11 18 01 36 25.2'}
{'2011 11 18 01 36 33.4'}
This file actually has 26 lines, but readtable only returns the last seven lines and somehow takes the table column name from the 19th line. This line has a value that should go into Var7, but so do lines in other files and they don't cause this problem.
I suspect the text file has a bad character in it, but I can't find it.
Any suggestions?
  5 Comments
dormant
dormant on 4 Apr 2022
Edited: dormant on 4 Apr 2022
I found some more examples and have spotted a pattern.
If the text file has some lines with values in the seventh column, it will read it succesfully if the last line is one of those with a value, as in the file 20160419-2010.txt.
If the last line doesn't have a value in the seventh column, but other lines do, it is read unsuccessfully.

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Accepted Answer

Stephen23
Stephen23 on 4 Apr 2022
T = readtable('20160419-2010.txt','NumHeaderLines',0)
T = 7×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____ ____ ____ ____ ____ ____ __________ 2016 4 19 20 10 51.3 {'RF?' } 2016 4 19 20 11 7.6 {0×0 char} 2016 4 19 20 11 30.4 {0×0 char} 2016 4 19 20 11 59.1 {0×0 char} 2016 4 19 20 13 29.4 {0×0 char} 2016 4 19 20 19 17.4 {0×0 char} 2016 4 19 20 20 17 {'RF?' }
T = readtable('20111118-0021.txt','NumHeaderLines',0)
T = 26×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____ ____ ____ ____ ____ ____ __________ 2011 11 18 0 21 59.2 {0×0 char} 2011 11 18 0 29 6.9 {0×0 char} 2011 11 18 0 31 6.8 {0×0 char} 2011 11 18 0 31 14.7 {0×0 char} 2011 11 18 0 32 12.7 {0×0 char} 2011 11 18 0 33 1.4 {0×0 char} 2011 11 18 0 34 32.4 {0×0 char} 2011 11 18 0 34 38.1 {0×0 char} 2011 11 18 0 34 43.5 {0×0 char} 2011 11 18 0 35 42.1 {0×0 char} 2011 11 18 0 37 29.1 {0×0 char} 2011 11 18 0 41 39.1 {0×0 char} 2011 11 18 1 33 43.7 {0×0 char} 2011 11 18 1 33 51.2 {0×0 char} 2011 11 18 1 33 60 {0×0 char} 2011 11 18 1 35 32.3 {0×0 char}
T = readtable('20080505-0553.txt','NumHeaderLines',0)
T = 31×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____ ____ ____ ____ ____ ____ __________ 2008 5 5 5 53 50.2 {0×0 char} 2008 5 5 5 53 59.4 {0×0 char} 2008 5 5 5 54 28.7 {0×0 char} 2008 5 5 5 54 41.9 {0×0 char} 2008 5 5 5 55 18.4 {0×0 char} 2008 5 5 5 55 24.2 {0×0 char} 2008 5 5 5 55 32.6 {0×0 char} 2008 5 5 5 55 55.2 {'RF?' } 2008 5 5 5 56 16.9 {0×0 char} 2008 5 5 5 56 28 {0×0 char} 2008 5 5 5 56 42.8 {0×0 char} 2008 5 5 5 56 57.3 {0×0 char} 2008 5 5 5 56 59.7 {0×0 char} 2008 5 5 5 57 9.7 {0×0 char} 2008 5 5 5 57 27.2 {0×0 char} 2008 5 5 5 57 32.1 {0×0 char}
  1 Comment
dormant
dormant on 4 Apr 2022
Fantastic, thank you.
I also managed to fix it by setting the format.
T = readtable( fileEventList, 'Format','%f %f %f %f %f %f %s' );

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