title: Sklearn Error, array with 4 dim. Estimator <=2
body: <p>I been trying import data from yahoo finance via panda then convert it to arrays via .as_matrix(), then as i input the data into the classifer to train, it gives me an error.</p>
  
  <pre><code>ValueError: Found array with dim 4. Estimator expected &lt;= 2.
  </code></pre>
  
  <p>This below is my code:</p>
  
  <pre><code>from sklearn import tree
  import pandas as pd
  import pandas_datareader.data as web
  
  df = web.DataReader('goog', 'yahoo', start='2012-5-1', end='2016-5-20')
  
  close_price = df[['Close']]
  
  ma_50 = (pd.rolling_mean(close_price, window=50))
  ma_100 = (pd.rolling_mean(close_price, window=100))
  ma_200 = (pd.rolling_mean(close_price, window=200))
  
  #adding buys and sell based on the values
  df['B/S']= (df['Close'].diff() &lt; 0).astype(int)
  close_buy = df[['Close']+['B/S']]
  closing = df[['Close']].as_matrix()
  buy_sell = df[['B/S']]
  
  
  close_buy = pd.DataFrame.dropna(close_buy, 0, 'any')
  ma_50 = pd.DataFrame.dropna(ma_50, 0, 'any')
  ma_100 = pd.DataFrame.dropna(ma_100, 0, 'any')
  ma_200 = pd.DataFrame.dropna(ma_200, 0, 'any')
  
  close_buy = (df.loc['2013-02-15':'2016-05-21']).as_matrix()
  ma_50 = (df.loc['2013-02-15':'2016-05-21']).as_matrix()
  ma_100 = (df.loc['2013-02-15':'2016-05-21']).as_matrix()
  ma_200 = (df.loc['2013-02-15':'2016-05-21']).as_matrix()
  buy_sell = (df.loc['2013-02-15':'2016-05-21']).as_matrix
  
  print(ma_100)
  clf = tree.DecisionTreeClassifier()
  x = [[close_buy,ma_50,ma_100,ma_200]]
  y = [buy_sell]
  
  clf.fit(x,y)
  </code></pre>