title: Matplot Numpy ValueError: setting an array element with a sequence
body: <p>I have the following code to try to create a 3d Plot for a dataset <a href="https://drive.google.com/file/d/1T0pwHO4q7YFhfejD00diq2dy12y_vmOo/view?usp=sharing" rel="nofollow noreferrer">YearlyKeywordsFrequency</a>. I cannot figure out why is this error coming</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  import pandas as pd
  from mpl_toolkits import mplot3d
  myData = pd.read_csv('counted-JOSAIC.csv', delimiter=',', skiprows=0,usecols=range(0,5))
  print(myData)
  item_list = list(myData.columns)            #Names of Columns
  item_list = item_list[1:]
  print(item_list)
  myData = np.array(myData)                   #Convert to numpy
  keywords = np.asarray(myData[:,0])          #Get the Keywords
  print(keywords)
  data = np.asarray(myData[:,1:])           #remove Keywords from data
  print(data.shape)
  print(data)
  ##################################################################################
  ###x=keyword
  ###y=year
  ###z=freq
  y=range(len(keywords))
  x=range(len(item_list))
  fig = plt.figure()
  ax = plt.axes(projection='3d')
  ax.contour3D(x, y, data, 50, cmap='binary')
  ax.set_yticklabels(keywords)
  ax.set_xticklabels(item_list)
  ax.set_xlabel('x')
  ax.set_ylabel('y')
  ax.set_zlabel('z');
  plt.show()
  </code></pre>
  
  <p>This code gives the following Results with error </p>
  
  <pre><code>              Kewords   freq-2015     ...       freq-2017   freq-2018
  0              energy         526     ...              89          97
  1               power         246     ...             170         125
  2            wireless         194     ...             121         144
  3        transmission         157     ...              77         106
  4             optimal         153     ...             100         110
  5        interference         136     ...             100          78
  6            spectrum         132     ...             126          29
  7          allocation         125     ...             143         101
  8          harvesting         123     ...               5          11
  9                node         114     ...              25          63
  10           capacity         106     ...              92          67
  11           cellular         102     ...              72          39
  12              relay          98     ...              20          35
  13             access          97     ...             138          98
  14            control          94     ...              50          87
  15               link          91     ...              62         105
  16              radio          91     ...              78          55
  17       localization          89     ...              11           3
  18           receiver          84     ...              20          38
  19             sensor          82     ...               4          21
  20            optical          80     ...               6          50
  21         simulation          79     ...              90          94
  22        probability          79     ...              51          44
  23                the          78     ...              59          64
  24               mimo          78     ...             192          49
  25             signal          76     ...              38          38
  26            sensing          76     ...              33           0
  27         throughput          73     ...              65          39
  28             packet          73     ...               8          38
  29      heterogeneous          71     ...              36          42
            ...         ...     ...             ...         ...
  8348            rated           0     ...               0           1
  8349              150           0     ...               0           1
  8350   highdefinition           0     ...               0           1
  8351      facilitated           0     ...               0           1
  8352              750           0     ...               0           1
  8353              240           0     ...               0           1
  8354         supplied           0     ...               0           1
  8355          robotic           0     ...               0           1
  8356      confinement           0     ...               0           1
  8357              jam           0     ...               0           1
  8358              8x6           0     ...               0           1
  8359        megahertz           0     ...               0           1
  8360        rotations           0     ...               0           1
  8361           sudden           0     ...               0           1
  8362            fades           0     ...               0           1
  8363           marine           0     ...               0           1
  8364          habitat           0     ...               0           1
  8365           probes           0     ...               0           1
  8366            uowcs           0     ...               0           1
  8367             uowc           0     ...               0           1
  8368  manchestercoded           0     ...               0           1
  8369        avalanche           0     ...               0           1
  8370              apd           0     ...               0           1
  8371              pin           0     ...               0           1
  8372          shallow           0     ...               0           1
  8373           harbor           0     ...               0           1
  8374           waters           0     ...               0           1
  8375            focal           0     ...               0           1
  8376              lcd           0     ...               0           1
  8377          display           0     ...               0           1
  
  [8378 rows x 5 columns]
  [' freq-2015', ' freq-2016', ' freq-2017', ' freq-2018']
  ['energy' 'power' 'wireless' ... 'focal' 'lcd' 'display']
  (8378, 4)
  [[526 747 89 97]
   [246 457 170 125]
   [194 248 121 144]
   ...
   [0 0 0 1]
   [0 0 0 1]
   [0 0 0 1]]
  Traceback (most recent call last):
  
    File "&lt;ipython-input-5-7d351bf710cc&gt;", line 1, in &lt;module&gt;
      runfile('C:/Users/Haseeb/Desktop/Report 5/PYTHON word removal/PlotingCharts.py', wdir='C:/Users/Haseeb/Desktop/Report 5/PYTHON word removal')
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 668, in runfile
  execfile(filename, namespace)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 108, in execfile
  exec(compile(f.read(), filename, 'exec'), namespace)
  
    File "C:/Users/Haseeb/Desktop/Report 5/PYTHON word removal/PlotingCharts.py", line 111, in &lt;module&gt;
  ax.contour3D(x, y, data, 50, cmap='binary')
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\mpl_toolkits\mplot3d\axes3d.py", line 2076, in contour
  self.auto_scale_xyz(X, Y, Z, had_data)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\mpl_toolkits\mplot3d\axes3d.py", line 494, in auto_scale_xyz
  self.xy_dataLim.update_from_data_xy(np.array([x, y]).T, not had_data)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\matplotlib\transforms.py", line 913, in update_from_data_xy
  path = Path(xy)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\matplotlib\path.py", line 127, in __init__
  vertices = _to_unmasked_float_array(vertices)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\matplotlib\cbook\__init__.py", line 1365, in _to_unmasked_float_array
  return np.asarray(x, float)
  
    File "e:\ProgramData\Anaconda3\lib\site-packages\numpy\core\numeric.py", line 492, in asarray
  return array(a, dtype, copy=False, order=order)
  
  ValueError: setting an array element with a sequence
  </code></pre>
  
  <p>I am trying to make a chart something like this <a href="https://i.stack.imgur.com/zJwKm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zJwKm.png" alt="Same Dataset 3d plot in Excel"></a> but i cant understand why is it giving an error when a 2d array is required and my array shape is (8374,4) so what is the problem.</p>