title: could not convert string to float
body: <p>I am very new to python and I only need it so I analyse some data for bio.<br>
  Please help on How I can fix the error below,<br>
  <code>could not convert string to float</code><br>
  I am trying to plot (Time, Distance)</p>
  
  <p>Here is some sample data:</p>
  
  <pre><code>Nematode No.    1           1              2          2
  No. of jumps    Time (sec)  Distance (mm)    Time        Distance
  1              0.195781141  0.893988392    1.25388    0.56569
  2              2.386623538  1.073359412    3.5848484  1.55656
  3              2.915538343  1.227371636    4.284848   2.34454545
  4              4.993603286  0.653631116    6.4545454  3.65445
  5              8.002735854  0.986036142    2.35554    0.2548545
  6             10.84267517   0.939671599    4.245454   0.5484848
  </code></pre>
  
  <p><strong>My code</strong> (yet)</p>
  
  <pre><code>from mmap import mmap,ACCESS_READ
  
  from xlrd import open_workbook
  from pylab import *
  from xlrd import open_workbook,XL_CELL_TEXT
  import csv
  from scipy import stats
  
  values = csv.reader(open('simple.csv', 'rb'), delimiter=',',skipinitialspace=True)
  
  for column in values:
      print column[1],column[2]
  
  Time = column[1]
  Distance = column[2]
  
  plot(Time,Distance)
  show()
  </code></pre>