How to get precision, recall and f-measure from confusion matrix in Python [duplicate]

Answer 1

If you have confusion matrix in the form of:

cmat = [[ 5,  7], 
        [25, 37]]

Following simple function can be made:

def myscores(smat): 
    tp = smat[0][0] 
    fp = smat[0][1] 
    fn = smat[1][0] 
    tn = smat[1][1] 
    return tp/(tp+fp), tp/(tp+fn)

Testing:

print("precision and recall:", myscores(cmat))

Output:

precision and recall: (0.4166666666666667, 0.16666666666666666)

Above function can also be extended to produce other scores, the formulae for which are mentioned on https://en.wikipedia.org/wiki/Confusion_matrix