title: how to load my own data or online dataset in python for training CNN or autoencoder?
body: <p>I'm trouble in a simple problem during loading dataset in python. I want to define function called <code>loading_dataset()</code> to use it in training auto encoder
  my code is</p>
  
  <pre><code>import matplotlib
  import numpy as np
  import tensorflow as tf
  import matplotlib.pyplot as plt
  from urllib import urlretrieve
  import cPickle as pickle
  import os
  
  import gzip
  rom urllib import urlretrieve
  import cPickle as pickle
  import os
  import gzip
  import matplotlib.cm as cm
  import theano
  import lasagne
  from lasagne import layers
  from lasagne.updates import nesterov_momentum
  from nolearn.lasagne import NeuralNet
  from nolearn.lasagne import visualize
  from sklearn.metrics import classification_report
  from sklearn.metrics import confusion_matrix
  #############################I tried to load data from open source
  def load_dataset():
      url = 'ftp://ftp nrg.wustl.edu/data/oasis_cross-sectional_disc2.tar.gz'
      filename ='oasis_cross-sectional_disc2.tar.gz'
      if not os.path.exists(filename):
          print("Downloading MNIST dataset...")
          urlretrieve(url, filename)
      with gzip.open(filename, 'rb') as f:
          data = pickle.load(f)
      X_train, y_train = data[0]
          X_val, y_val = data[1]
          X_test, y_test = data[2]
          X_train = X_train.reshape((-1, 1, 28, 28))
          X_val = X_val.reshape((-1, 1, 28, 28))
          X_test = X_test.reshape((-1, 1, 28, 28))
          y_train = y_train.astype(np.uint8)
          y_val = y_val.astype(np.uint8)
          y_test = y_test.astype(np.uint8)
          return X_train, y_train, X_val, y_val, X_test, y_test
  X_train, y_train, X_val, y_val, X_test, y_test = load_dataset()
  </code></pre>
  
  <p>downloading MNIST dataset...</p>
  
  <pre><code>Traceback (most recent call last):
    File "&lt;pyshell#46&gt;", line 1, in &lt;module&gt;
      X_train, y_train, X_val, y_val, X_test, y_test = load_dataset()
    File "&lt;pyshell#45&gt;", line 6, in load_dataset
      urlretrieve(url, filename)
    File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib.py", line 98, in urlretrieve
      return opener.retrieve(url, filename, reporthook, data)
    File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib.py", line 245, in retrieve
      fp = self.open(url, data)
    File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib.py", line 213, in open
      return getattr(self, name)(url)
    File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib.py", line 526, in open_ftp
      host = socket.gethostbyname(host)
  IOError: [Errno socket error] [Errno 8] nodename nor servname provided, or not known
  </code></pre>
  
  <p>this error appeared</p>
  
  <p>I also tried to load data from my desktop using this code
  for path, dirs, files in os.walk(pat):
  for filename in files:
              fullpath = os.path.join(path, filename)
              with open(fullpath, 'r') as f:
                      s=np.load(f)
                  data = f.read()
                      print data</p>
  
  <p>but I failed to load data as values for X_train, y_train, X_val, y_val, X_test, y_test 
  I don't know if I should compress dataset in .pkl.gz or use different function for loading data
  could you help me?</p>