title: numpy.float64' object is not callable in auc(recall, precision)
body: <p>The program throws <code>['numpy.float64' object is not callable]</code> error when I run :</p>
  
  <pre><code>auc(recall, precision)
  </code></pre>
  
  <p>I was able to run this successfully until today. I'd appreciate any help on this, thanks! I also tried it with () but it didn't work.</p>
  
  <pre><code>fit_logreg = LogisticRegression(class_weight='balanced', verbose=0)
  
  fit_logreg.set_params(penalty = 'l2',
                    C = 0.00001, 
                    n_jobs=-1,
                    verbose=0
                    )
  ###########################################################
  ###4#TRAIN THE FITTING MODEL ON THE TRAINING DATASET###
  ###########################################################
  # fit a model
  fit_logreg.fit(trainX, trainy)
  
  # score the test dataset
  
  predictions_logreg = fit_logreg.predict(testX)
  #predictions_logreg = predictions_logreg.values.ravel() 
  
  ###########################################################
  ###5#OOB ERROR AND CLASSIFICATION SUCCESS METRICS###
  ###########################################################
  
  ##ROC AUC SCORE
  roc_auc_score(testy, predictions_logreg,average='macro')
  
  ##RECALL-PRECISION CURVE
  
  # predict probabilities
  probs = fit_logreg.predict_proba(testX)
  # keep probabilities for the positive outcome only
  probs = probs[:, 1]
  # predict class values
  yhat = predictions_logreg
  # calculate precision-recall curve
  precision, recall, thresholds = precision_recall_curve(testy, probs)
  # calculate F1 score
  f1 = f1_score(testy, yhat)
  
  # calculate precision-recall AUC
  auc(recall, precision)
  </code></pre>
  
  <p>This is the error I am getting :</p>
  
  <pre><code>TypeErrorTraceback (most recent call last)
  &lt;ipython-input-1-74f87a22f33a&gt; in &lt;module&gt;()
       68 # calculate precision-recall AUC
       69 #auc = auc(recall, precision)
  ---&gt; 70 auc(recall, precision)
  
  TypeError: 'numpy.float64' object is not callable
  </code></pre>