How to Get AUC Value Under ROC Plot for Factor Data (Not Numeric 0 & 1) in R for Prediction Mapping?

Exercise code is below:
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# Step 3 Plot ROC curves
library(pROC)
# the model is used to predict the test data. However, you should ask for type="prob" here

## Since you have probabilities, use them to get the most-likely class.
# predict class and then attach test class
head(predictions1)

# Now, let's see how to plot the ROC curves. For each class, convert the multi-class problem into a binary problem. Also,
# call the roc() function specifying 2 arguments: i) observed classes and ii) class probability (instead of predicted class).
# 1 ROC curve, Moderate, Good, UHeal vs non Moderate non Good non UHeal

# calculating the values of AUC for ROC curve
print(results)
legend("topleft",c("AUC = 0.85 "),fill=c("red"),inset = (0.42))
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#GIS
#Prediction
#Machine_learning