title: Logistic Regression get Value error could not convert string to float: '?'
body: <p>I am very new at this stuff.  This is from a course I am taking;
  I need to fit the Logistic Regression classifier</p>
  
  <p>I enter </p>
  
  <pre><code>from sklearn.linear_model import LogisticRegression
  C=1.0
  classifier = LogisticRegression(C=C, penalty='l1')
  
  classifier.fit(x, y)
  </code></pre>
  
  <p>and get a Value Error</p>
  
  <pre><code>ValueError                                Traceback (most recent call last) &lt;ipython-input-33-9d4de811daf9&gt; in &lt;module&gt;()
  ----&gt; 1 classifier.fit(x, y)
  
  ~\Anaconda3\lib\site-packages\sklearn\linear_model\logistic.py in fit(self,  X, y, sample_weight)    1214     1215         X, y = check_X_y(X, y, accept_sparse='csr', dtype=_dtype,
  -&gt; 1216                          order="C")    1217         check_classification_targets(y)    1218         self.classes_ = np.unique(y)
  
  ~\Anaconda3\lib\site-packages\sklearn\utils\validation.py in check_X_y(X, y,  accept_sparse, dtype, order, copy, force_all_finite, ensure_2d, allow_nd,  multi_output, ensure_min_samples, ensure_min_features, y_numeric,  warn_on_dtype, estimator)
      571     X = check_array(X, accept_sparse, dtype, order, copy,  force_all_finite,
      572                     ensure_2d, allow_nd, ensure_min_samples,
  --&gt; 573                     ensure_min_features, warn_on_dtype, estimator)
      574     if multi_output:
      575         y = check_array(y, 'csr', force_all_finite=True,  ensure_2d=False,
  
  ~\Anaconda3\lib\site-packages\sklearn\utils\validation.py in  check_array(array, accept_sparse, dtype, order, copy, force_all_finite,  ensure_2d, allow_nd, ensure_min_samples, ensure_min_features, warn_on_dtype,  estimator)
      431                                       force_all_finite)
      432     else:
  --&gt; 433         array = np.array(array, dtype=dtype, order=order, copy=copy)
      434 
      435         if ensure_2d:
  
  ValueError: could not convert string to float: '?'
  </code></pre>
  
  <p>Please help</p>