Keep getting "unable to use a value of type string as an index" error and I'm unsure why

As stated in the title I keep getting "Unable to use a value of type string as an index" error for one line of code and I'm unsure what I am doing wrong. The code is as follows:

sc1 = [sc(1:end,"custID"),sc(1:end,"CLAGE"), sc(1:end,"DELINQ") , sc(1:end,"DEROG") , sc(1:end,"DEBTINC"), sc(1:end,"VALUE") , sc(1:end,"NINQ"), sc(1:end,"BAD")]; %%% This is the line that is giving me the error

scorecard1 = creditscorecard(sc1,"IDVar","custID","BinMissingData",true);

scorecard1 = modifybins(scorecard1,'DEBTINC','CutPoints',[ 30 40]);

scorecard1 = modifybins(scorecard1,'VALUE','CutPoints',[50000 100000 150000]);

scorecard1 = modifybins(scorecard1,'DEROG','CutPoints', [1 2 3]);

scorecard1 = modifybins(scorecard1,'DELINQ','CutPoints', [1 2 3]);

scorecard1 = modifybins(scorecard1,'CLAGE','CutPoints',[100 200 300]);

scorecard1 = modifybins(scorecard1,'NINQ','CutPoints',[1 2 3]);

scorecard1 = fitmodel(scorecard1);

Thanks!

[Jan]

What is sc? Why do you assume, that "sc(1:end,"custID")" is a valid syntax?

Please format your code using the tools above the section for editing. Then it would be easier to seem which line is failing.

Answer 1

[Hari]

Hi Adian,

I understand that you are encountering an error related to using a value of type string as an index in MATLAB.

I assume that ‘sc’ is a matrix. To resolve this issue, you can modify your code to convert the matrix into a table using the “array2table” function. This allows for indexing using string column names without encountering the error. Here is an example of how you can do that:

% Convert sc to a table if it is not already
if ~istable(sc)
    sc = array2table(sc); % Assuming sc is a matrix, convert it to a table
end

Once ‘sc’ is converted to table you can perform indexing operations using strings.

% Perform the indexing operation
sc1 = [
    sc(:, "custID"), 
    sc(:, "CLAGE"), 
    sc(:, "DELINQ"), 
    sc(:, "DEROG"), 
    sc(:, "DEBTINC"), 
    sc(:, "VALUE"), 
    sc(:, "NINQ"), 
    sc(:, "BAD")];

When I did the above modification, your code ran without errors and produced output.

Output observed:

Generalized linear regression model:

logit(BAD) ~ 1

Distribution = Binomial

Estimated Coefficients:

Estimate SE tStat pValue

________ _______ _______ _______

(Intercept) 0.40547 0.91287 0.44416 0.65692

5 observations, 4 error degrees of freedom

Dispersion: 1

Refer to the documentation of “array2table” function for more information.

Convert homogeneous array to table - MATLAB array2table (mathworks.com)

Hope this helps!