How to change target class when using CLASSPERF

Dear all,

I wonder, How to specify a particular label as the target class when using CLASSPERF. For example, I want to indicate that Label 1 and 0 for Classout (classifier output) as Positive and Negative for disease, respectively. This is because, I follow the convention where, for classifier output, label equal to 1 as positive for disease. However, I notice, Matlab treat 0 as positive for output. From link, it seem we change the default by adjusting TargetClasses. However, I dont know how to exactly do it.

truelabels=[1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 0 0];
classout=  [1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 NaN];
CP = classperf(truelabels, classout);

Answer 1

[Walter Roberson]

scats = {'Negative', 'Positive'};
struelabels = scats(truelabels + 1);
sclassout = scats((classout==1) + 1);
sclassout(isnan(classout)) = {'Undefined'};

CP = classperf(struelabels, sclassout);

There might be a better way.

[balandong]

Hi Walter, As usual, your suggestion always amaze me,very neat. Thank you