Error using ==> load Number of columns on line 1 of ASCII file must be the same as previous lines.

My text file is in the current directory.

This is my m-file.

clear all
close all
fontsize = 12;
myfile = 'homework0file.txt';
mydata = load(myfile);
x = mydata(:,1);
y = mydata(:,2);

This is my txt file

% column 1 is time in seconds 
% column 2 is distance in cm 
    1    3.35959  
    2   -9.14439  
    3   -2.67077  
    4  -11.58844  
    5  -11.13751  
    6   -5.16964  
    7   -6.10970  
    8  -17.84179  
    9  -20.72885  
   10  -17.68507  
   11  -19.91041  
   12   -9.58301  
   13  -12.87876  
   14  -12.57608  
   15  -19.52674  
   16   -4.54303  
   17   -6.92412  
   18  -10.62736  
   19   -2.85174  
   20  -16.11786  
   21   -7.09710  
   22   -7.56091  
   23   -7.55522  
   24  -15.10473  
   25   -7.71212  
   26  -13.60417  
   27  -16.27512  
   28  -18.42288  
   29   -2.73529  
   30  -15.92161  
   31  -11.21040  
   32  -18.46056  
   33  -12.07989  
   34  -32.62426  
   35  -17.60871  
   36  -19.98505  
   37  -17.10116  
   38  -11.49287  
   39  -12.27743  
   40    3.61078  
   41  -14.00241  
   42  -11.75023  
   43  -20.98521  
   44  -13.34168  
   45  -19.36584  
   46   -9.78791  
   47   -4.02839  
   48   -7.17023  
   49  -14.90434  
   50  -21.41380  
   51    0.22009  
   52    4.35030  
   53   -9.15650  
   54  -16.92931  
   55   -1.61560  
   56  -14.14859  
   57  -13.28867  
   58   -3.79536  
   59  -19.69654  
   60  -23.69728  
   61   -7.05521  
   62   -7.19483  
   63   -9.33400  
   64   -6.52321  
   65   -2.42432  
   66   -3.20687  
   67  -13.97999  
   68   -4.33020  
   69   -8.78727  
   70  -13.53880  
   71  -18.35314  
   72   -5.47120  
   73  -12.47536  
   74   -9.67496  
   75  -15.55063  
   76  -20.85360  
   77   -8.79890  
   78  -10.43497  
   79   -1.60680  
   80   -4.38807

when the m-file is run

the error in the title shows up

WHY DO I WASTE SO MUCH TIME ON SUCH A POINTLESS ERROR

[Oleg Komarov]

Please format the code and the data: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup#answer_18099

Answer 1

[Fangjun Jiang]

What version of MATLAB are you using? I tried on R2007b. It is fine.

>> mydata=load('test.txt')

mydata =

      1.0000    3.3596
      2.0000   -9.1444
      3.0000   -2.6708
      4.0000  -11.5884

Or try importdata()

>> a=importdata('test.txt')

a =

      1.0000    3.3596
      2.0000   -9.1444
      3.0000   -2.6708
      4.0000  -11.5884

Or

>> [x,y]=textread('test.txt','%f %f','headerlines',2);
>> [x(1:5) y(1:5)]

ans =

      1.0000    3.3596
      2.0000   -9.1444
      3.0000   -2.6708
      4.0000  -11.5884
      5.0000  -11.1375

Answer 2

[Walter Roberson]

load() is not suitable for files that contain text (even in the form of matlab comments.)

You should use textscan() or dlmread(), specifying to them that you want to skip two header lines or that you want to treat '%' as indicating a comment.

[Olav]

Actually, dlmread doesn't work either; within dlmread it says

%   All data in the input file must be numeric. DLMREAD does not operate 
%   on files containing nonnumeric data, even if the specified rows and
%   columns for the read contain numeric data only.

textscan() does seem to be able to do it, but the output will be in arrays.

[Walter Roberson]

True.

[Abhishek H P]

Hello Walter,

You gave insight on trying to convert .dat to .mat however I got an error

'Error using load
Number of columns on line 1 of ASCII file
C:\xyz.dat
must be the same as previous lines.'

But .dat has nearly 50,000 rows and 1000 columns

Thanks in advance

[Walter Roberson]

Abhishek H P, load is not suitable for text files. I suggest you try readtable()

[Jan]

@Walter: With the -ascii flag, load reads text files, but it accepts only the format used by save -ascii. Therefore readtable is a better choice.

[Abhishek H P]

@ Walter,

I tried readtable(Filename.dat) and encountered below issues....

Error: The input character is not valid in MATLAB statements or expressions.

[Walter Roberson]

readtable('Filename.dat', 'FileType', 'text')

[zhe wang]

dlm read command would give me back the command:

DELIMITER must be a single character.

instead the xlsread command would doing just fine

[Walter Roberson]

We would need to see your dlmread call.

[Walter Roberson]

I was probably wrong in my initial answer: % comments at the beginning of lines are accepted by load of text files.