title: How do I remove future warning regarding n_estimators will change from 10 in version 0.20 to 100 in 0.22?
body: <p>Running an otherwise well-functioning code, I keep getting the following message in the console in PyCharm (view 'Response in console': FutureWarning: The default value of n_estimators will change from 10 in version 0.20 to 100 in 0.22. "10 in version 0.20 to 100 in 0.22.", FutureWarning)). Also, the warning is listed several times.</p>
  
  <p>Looking here and there, I understand that a way to remove it is to change n_estimators from 10 to 100, thereby expanding 'trees in the forest'. Yet several attempts to do that failed.</p>
  
  <pre><code>from sklearn.ensemble import RandomForestClassifier
  model = RandomForestClassifier(n_estimators=100) &lt;== added this line; not sure, if ok!
  random_forest_classifier = RandomForestClassifier()
  random_forest_classifier.fit(X_train, y_train)
  y_pred_rfc = random_forest_classifier.predict(X_test)
  
  import warnings
  warnings.simplefilter(action='ignore', category=FutureWarning)
  warnings.simplefilter(action='ignore', category=DeprecationWarning)
  warnings.simplefilter(action='ignore', category=RuntimeWarning)
  
  print("\nConfusion Matrix")
  cm_random_forest_classifier = confusion_matrix(y_test,y_pred_rfc)
  print(cm_random_forest_classifier, end="\n\n")
  
  print("\nCalculating the accuracy from the confusion matrix for Random Forest")
  numerator = cm_random_forest_classifier[0][0] + cm_random_forest_classifier[1][1]
  denominator = sum(cm_random_forest_classifier[0]) + sum(cm_random_forest_classifier[1])
  acc_rfc = (numerator/denominator) * 100
  print("Accuracy of Random Forest: ", round(acc_rfc,2),"%")
  
  cross_val_rfc = cross_val_score(estimator=RandomForestClassifier(), X=X_train, y=y_train, cv=10, n_jobs=-1)
  print("Cross Validation Accuracy of Random Forest: ",round(cross_val_rfc.mean() * 100 , 2),"%")
  </code></pre>
  
  <p>Response in console:</p>
  
  <pre><code>Confusion Matrix
  [[1722   51]
   [ 166   48]]
  
  Calculating the accuracy from the confusion matrix for Random Forest
  Accuracy of Random Forest:  89.08 %
  C:\Users\....\Programs\Python\Python37-64\lib\site-packages\sklearn\ensemble\forest.py:245: FutureWarning: The default value of n_estimators will change from 10 in version 0.20 to 100 in 0.22. "10 in version 0.20 to 100 in 0.22.", FutureWarning)
  Cross Validation Accuracy of Random Forest:  89.71 %
  </code></pre>