how to compare non numerical values or character strings element-wise between a table and a one dimensional array ?

IrisD = readtable('irisdata.csv');
classes = categorical(IrisD{:,5});
Icats = categories(classes);
setosa = IrisD((IrisD(:,5)==Icats(1)),:);      
    Ttest1 = setosa(1:40,:);
    Ttrain1 = setosa(41:50,:);
versicolor = IrisD((IrisD(:,5)==Icats(2)),:);   
    Ttest2 = versicolor(1:40,:);
    Ttrain2 = versicolor(41:50,:);
virginica = IrisD((IrisD(:,5)==Icats(3)),:);   
    Ttest3 = virginica(1:40,:);
    Ttrain3 = virginica(41:50,:);
    Ttest = [Ttest1; Ttest2; Ttest3];
    Ttrain = [Ttrain1; Ttrain2; Ttrain3];

I am getting this error: Undefined operator '==' for input arguments of type 'table'.

I am trying to split the Iris database into a training and testing dataset, with the first 40 values of each class being in the testing dataset and the remaining 10 for each class be in the training dataset.

[madhan ravi]

{} instead of ()

[Apurva Jariwala]

thanks for the response

setosa = IrisD((IrisD(:,5)==Icats{1}),:);      

like that ?

still getting the same error

[madhan ravi]

setosa = IrisD(strcmp(IrisD{:,5},Icats(1)),:);     % if it doesn't work attach your data file 

[comment moved to answer section]

[Apurva Jariwala]

Thanks a lot!

It worked!

[Peter Perkins]

Apurva, IrisD{:,5} certainly will work.

But I suggest that you use names, and dot indexing, and ==. So you code becomes

setosa = IrisD(IrisD.Species == Icats(1),:)

or maybe even

setosa = IrisD(IrisD.Species == 'setosa',:)

Isn't that nicer?

[Apurva Jariwala]

Yes it does.

Thank you very much for the response.

Answer 1

[madhan ravi]

https://in.mathworks.com/matlabcentral/answers/450866-how-to-compare-non-numerical-values-or-character-strings-element-wise-between-a-table-and-a-one-dime#comment_682761