f1_score() takes 2 positional arguments but 3 positional arguments (and 1 keyword-only argument) were given

Question

 from sklearn.metrics import f1_score


 F1_score = f1_score(lab2d, pred2d, [0, 1, 2, 3], average=None)
print("Validation Dice Coefficient.... ")
print("Background:", F1_score[0])
print("CSF:", F1_score[1])
print("GM:", F1_score[2])
print("WM:", F1_score[3])
 ```

This is the error

f1_score() takes 2 positional arguments but 3 positional arguments (and 1  keyword-only argument) were given

I tried to pass the arguments in diffrerent ways but still got the same error

Answer 1

As the documentation for version 1.2.0 states, you need to call the function like

from sklearn.metrics import f1_score
y_true = [0, 1, 2, 0, 1, 2]
y_pred = [0, 2, 1, 0, 0, 1]
f1_score(y_true, y_pred, average='macro')

Please note that it accepts 3 arguments: y_true , y_pred and keyword argument average . You are trying to put one extra argument in: [0, 1, 2, 3] . Either it or one of the previous two arguments ( lab2d or pred2d ) should be removed.