title: Create a data frame from object
body: <p>I'm given with a collection of objects and need to save their attributes in a data frame. These objects all have the same attributes, but different values.</p>
  
  <p>I was trying</p>
  
  <pre><code>dicts = [x.__dict__ for x in objectCollection]
  df = pd.concat(dicts)
  </code></pre>
  
  <p>but that would give me </p>
  
  <pre><code>TypeError: cannot concatenate a non-NDFrame object
  </code></pre>
  
  <p>Following, for reproduction purposes, my <code>r</code> object (it contains 4 dictionaries)</p>
  
  <pre><code>In[94]: r
  Out[94]: 
  [{'JB': 0.5261750636924186,
    'JBar': 0.5261750636925998,
    'U': 0.3294737627050343,
    'VB': 0,
    'VBar': 0,
    'WB': 0.3879376586708586,
    'WBar': 0.38793765867087865,
    'YB': 0.48616322013005736,
    'YBar': 0.4861632201302899,
    'pB': 1,
    'pBar': 1.0000000000002274,
    'theta': 30.452217802750784,
    'thetaB': 15.226108901371752,
    'thetaBar': 15.226108901379034,
    'u': 0.027673559739652746,
    'vB': 0.4213606342845696,
    'vBar': 0.4213606342847711,
    'wB': 0.40542217802756686,
    'wBar': 0.4054221780275895},
   {'JB': 0.591730026927601,
    'JBar': 0.5888459364503311,
    'U': 0.3574380470030322,
    'VB': 0,
    'VBar': 0,
    'WB': 0.4133529860815169,
    'WBar': 0.42286537327529117,
    'YB': 0.4450754942945968,
    'YBar': 0.4420654404537785,
    'pB': 1,
    'pBar': 1.0068090684451363,
    'theta': 35.72497708330982,
    'thetaB': 17.92309565619036,
    'thetaBar': 17.801881427119454,
    'u': 0.02414497177678684,
    'vB': 0.43275263877136705,
    'vBar': 0.4298259246315051,
    'wB': 0.43134506957181085,
    'wBar': 0.44209406710077587},
   {'JB': 0.46774949304709174,
    'JBar': 0.783373528458816,
    'U': 0.4259229207218348,
    'VB': 0,
    'VBar': 0,
    'WB': 0.47789508661595614,
    'WBar': 0.5129644238839255,
    'YB': 0.5805290540642507,
    'YBar': 0.39605190181885574,
    'pB': 1,
    'pBar': 1.4657903456561598,
    'theta': 39.39305475097706,
    'thetaB': 12.929841051766449,
    'thetaBar': 26.463213699210606,
    'u': 0.02341904411689341,
    'vB': 0.302804518015738,
    'vBar': 0.6197431690965912,
    'wB': 0.4948305475091409,
    'wBar': 0.5414095820747569},
   {'JB': 0.5246012340492012,
    'JBar': 0.8731358801035817,
    'U': 0.4675627478175433,
    'VB': 0,
    'VBar': 0,
    'WB': 0.5155637079793887,
    'WBar': 0.5645778456068301,
    'YB': 0.5312340916010532,
    'YBar': 0.3593021864121634,
    'pB': 1,
    'pBar': 1.4785161674233223,
    'theta': 45.929330938192074,
    'thetaB': 15.162892309068837,
    'thetaBar': 30.766438629123233,
    'u': 0.020410094185461556,
    'vB': 0.3094760601521056,
    'vBar': 0.6279459101716279,
    'wB': 0.5334306672268627,
    'wBar': 0.5960674456434281}]
  </code></pre>