title: Plotting graph from CSV
body: <p>Im looking for a bit of help, Im really new to Python and dont know if it just making thngs harder for myslef or what. Im trying to plot a simple line graph from a csv file.
  Ive tried a number of approaches but all return the error :
  ValueError: could not convert string to float:</p>
  
  <p>This is the code if seeming to get the best with</p>
  
  <pre><code>import csv`
  import pylab as pl
  import numpy as np
  matplotlib.dates as mdates
  with open('D:/growth_rate.csv') as csvfile:
       readCSV = csv.reader(csvfile, delimiter=',')
  
  for row in readCSV:
      print (row)
  a= (row)
  np.shape(a)
  x,y = np.loadtxt('D:/growth_rate.csv', delimiter = ',', unpack=True,
                           converters = {0: mdates.strpdate2num('%d/%m/%Y')})
  </code></pre>
  
  <p>Ive also tried the csv reader approach, but similar problem</p>
  
  <pre><code>a = zip(*csv.reader(open('D:/growth_rate.csv', 'rb')))
  csv.writer(open('D:/growth_rate.csv', "wb")).writerows(a)
  
  print a
  </code></pre>
  
  <p>I dont know if its a problem with the csv file, it originally was a xls file, with a company headers and other nonsense, so i put it into a csv and also tried a txt file.  Either that or im missing something really obvious,</p>
  
  <p>Any help, greatly appreciated. </p>