error using readtable : Array indices must be positive integers or logical values.

Hi,

I have a simple tab-delimited file text which looks like :

Month H_Gh H_Dh H_Bn Ta

Jan 33 17 55 0.5

Feb 52 29 60 1.4

Mar 97 51 97 5.6

Apr 123 60 113 9.7

I want to create a table with readtable(filename) Matlab function. So I have tried this directly into console

T = readtable('data.txt', 'Delimiter', '\t')

Error using readtable (line 197)
Array indices must be positive integers or logical values.

Note: readtable detected the following parameters:
'HeaderLines', , 'ReadVariableNames', true, 'Format', ''

I have tried with others text files. If all rows in the file are the same types, readtable works well, but if a line contains string and numbers (like my file), this error pop. Anyone have an solution to propose ?

I'm on windows7 with R2018a.

[Stephen23]

It works on this forum using your sample file:

T = readtable('simpleData.txt', 'Delimiter', '\t')

T = 12×5 table
     Month     H_Gh    H_Dh    H_Bn     Ta 
    _______    ____    ____    ____    ____

    {'Jan'}     33      17      55      0.5
    {'Feb'}     52      29      60      1.4
    {'Mar'}     97      51      97      5.6
    {'Apr'}    123      60     113      9.7
    {'May'}    161      91     115     13.7
    {'Jun'}    178      79     160       18
    {'Jul'}    176      76     165     19.3
    {'Aug'}    153      67     148     18.7
    {'Sep'}    105      52     102     14.5
    {'Oct'}     63      42      51     10.2
    {'Nov'}     33      18      49      4.9
    {'Dec'}     24      16      32      1.2

[Arthur]

Indeed, that works on this forum by running with matlab licence R2022a, but i'm developing with R2018a.When I run it on command window the error mentioned above pops.

Answer 1

[Mathias Smeets]

This seems to work:

opts = detectImportOptions('simpleData.txt');
tbl = readtable('simpleData.txt',opts);

I hope this is what you are asking :)

[Arthur]

Thanks for this proposal. When I run first line

>> opts = detectImportOptions('C:\tmp\simpleData.txt');
Array indices must be positive integers or logical values.

Error in matlab.io.spreadsheet.internal.detectTypes (line 54)
    types = typenames(dominateType);

Error in matlab.io.internal.text.getTextOpts (line 85)
    [types, metaRows, emptyCols] = matlab.io.spreadsheet.internal.detectTypes(ids,emptyColType);

Error in detectImportOptions (line 268)
        opts = matlab.io.internal.text.getTextOpts(filename,emptyColType,args);
 
54      types = typenames(dominateType);

I use pause on error and dominateType from matlab.io.spreadsheet.internal.detectTypes equals to 1.5 but used as an array indice.

matlab.io.spreadsheet.internal.detectTypes file is not editable

[Mathias Smeets]

Try clearing your variables:

clear all

This might very maybe help

[Arthur]

Unfortunately

>> clear all
>> opts = detectImportOptions('C:\tmp\simpleData.txt');
Array indices must be positive integers or logical values.

Error in matlab.io.spreadsheet.internal.detectTypes (line 54)
    types = typenames(dominateType);

Error in matlab.io.internal.text.getTextOpts (line 85)
    [types, metaRows, emptyCols] = matlab.io.spreadsheet.internal.detectTypes(ids,emptyColType);

Error in detectImportOptions (line 268)
        opts = matlab.io.internal.text.getTextOpts(filename,emptyColType,args);

I consider made a function by myself to parse file...

[Mathias Smeets]

Are you sure there isn't some other function in your path that is called 'detectImportOptions' or something like that? Are you sure your code is calling the built in matlab function?

[Arthur]

When I run in debug, the detectImportOptions function called is the one situated at 'C:\Program Files\MATLAB\R2018a\toolbox\shared\io\detectImportOptions.m'. So I guess yes

[Mathias Smeets]

Very strange, I looked it up online and it seems like some people, as you can see here, solved some similar problems by reinstalling. But my suggestion would be to wait a bit until other people answer.

Sorry I can not help you further.

[Arthur]

I will try, thank you for your time