title: pca.inverse_transform in sklearn
body: <p>after fitting my data into 
  X = my data</p>
  
  <pre><code>pca = PCA(n_components=1)
  pca.fit(X)
  X_pca = pca.fit_transform(X)
  </code></pre>
  
  <p>now X_pca has one dimension.</p>
  
  <p>When I perform inverse transformation by definition isn't it supposed to return to original data, that is X, 2-D array?</p>
  
  <p>when I do </p>
  
  <pre><code>X_ori = pca.inverse_transform(X_pca)
  </code></pre>
  
  <p>I get same dimension however different numbers.</p>
  
  <p>Also if I plot both X and X_ori they are different.</p>