How to prevent readtable excluding rows with "NA"?

I have a textfile in this format (also attached) produced from an image processing loop, which when read in using readtable(), gives me the resulting table.

% Image	X	Y	Area	Circularity	Extent	Height	Width
% IMG_0560.jpg	NA	NA	NA	NA	NA	NA	NA
% IMG_0561.jpg	NA	NA	NA	NA	NA	NA	NA
% IMG_0562.jpg	NA	NA	NA	NA	NA	NA	NA
% IMG_0565.jpg	2388.9432	1028.7865	740	1.0291	0.83053	2736	3648
% IMG_0566.jpg	3020.4438	1152.3859	1433	0.99398	0.7788	2736	3648
% IMG_0567.jpg	NA	NA	NA	NA	NA	NA	NA
% IMG_0568.jpg	3512.2915	878.88912	1434	1.0338	0.83275	2736	3648

readtable("C:\Desktop\exampletxt.txt");

%       Image               X         Y       Area    Circularity    Extent     Height    Width
%     ________________    ______    ______    ____    ___________    _______    ______    _____
% 
%     {'IMG_0565.jpg'}    2388.9    1028.8     740       1.0291      0.83053     2736     3648 
%     {'IMG_0566.jpg'}    3020.4    1152.4    1433      0.99398       0.7788     2736     3648 
%     {'IMG_0567.jpg'}       NaN       NaN     NaN          NaN          NaN      NaN      NaN 
%     {'IMG_0568.jpg'}    3512.3    878.89    1434       1.0338      0.83275     2736     3648 

As you can see it excludes the first few rows that contain NAs, which I need to be included, as it has done correctly for the third row. Is there a way to do this with readtable? Ultimately, all I need is the first column, as I'm then using contain() to see if a given image name exists in this textfile.

Answer 1

[Star Strider]

Try this —

C1 = readcell('https://www.mathworks.com/matlabcentral/answers/uploaded_files/629630/exampletxt.txt');
VN = C1(1,:);
C1a = C1(2:end,:);
NAI = strcmp(C1(2:end,:), 'NA');
C1a(NAI) = {'NaN'};
T1 = cell2table(C1a, 'VariableNames',VN)

T1 = 7×8 table
         Image                X                 Y             Area      Circularity      Extent       Height      Width  
    ________________    ______________    ______________    ________    ___________    __________    ________    ________

    {'IMG_0560.jpg'}    {'NaN'       }    {'NaN'       }    {'NaN' }    {'NaN'   }     {'NaN'   }    {'NaN' }    {'NaN' }
    {'IMG_0561.jpg'}    {'NaN'       }    {'NaN'       }    {'NaN' }    {'NaN'   }     {'NaN'   }    {'NaN' }    {'NaN' }
    {'IMG_0562.jpg'}    {'NaN'       }    {'NaN'       }    {'NaN' }    {'NaN'   }     {'NaN'   }    {'NaN' }    {'NaN' }
    {'IMG_0565.jpg'}    {[2.3889e+03]}    {[1.0288e+03]}    {[ 740]}    {[1.0291]}     {[0.8305]}    {[2736]}    {[3648]}
    {'IMG_0566.jpg'}    {[3.0204e+03]}    {[1.1524e+03]}    {[1433]}    {[0.9940]}     {[0.7788]}    {[2736]}    {[3648]}
    {'IMG_0567.jpg'}    {'NaN'       }    {'NaN'       }    {'NaN' }    {'NaN'   }     {'NaN'   }    {'NaN' }    {'NaN' }
    {'IMG_0568.jpg'}    {[3.5123e+03]}    {[  878.8891]}    {[1434]}    {[1.0338]}     {[0.8327]}    {[2736]}    {[3648]}

.

[BC]

Thanks for the help, this works!

[Star Strider]

As always, my pleasure!

If you only need to read the first column:

filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/629630/exampletxt.txt';
T1 = readtable(filename,"Format","%s%*s%*s%*s%*s%*s%*s%*s")

T1 = 7×1 table
         Image      
    ________________

    {'IMG_0560.jpg'}
    {'IMG_0561.jpg'}
    {'IMG_0562.jpg'}
    {'IMG_0565.jpg'}
    {'IMG_0566.jpg'}
    {'IMG_0567.jpg'}
    {'IMG_0568.jpg'}

The ‘*’ between the ‘%’ and the format descriptor omits reading that field.

[BC]

Thanks for another useful tip, makes things a bit tidier if using that approach!

[Star Strider]

As always, my pleasure!