Question

the file.xml contains the following data structure:

<table>
 <row>
   <x>10</x>
   <t>10:00</t>
</row>
<row>
   <x>20</x>
   <t>10:05</t>
</row>
</table>

I have hundred of x,t pairs. I need to plot x vs. t.
I would be thankful if you can help me to solve the problem with python and matplotlib.

Answer 1

import lxml.etree as ET
import matplotlib.pyplot as plt

text='''\
<table>
 <row>
   <x>10</x>
   <t>10:00</t>
</row>
<row>
   <x>20</x>
   <t>10:05</t>
</row>
</table>
'''

def convert_t(text):
    a,b=map(float,t.split(':'))
    return a+b/60.0

doc=ET.fromstring(text)
x=[float(x) for x in doc.xpath('//x/text()')]
t=[convert_t(t) for t in doc.xpath('//t/text()')]
plt.plot(x,t)
plt.show()

• The above code assumes 10:05 means something like 10 minutes, 5
  seconds. It converts this to a float using convert_t.
• A closing </table> was added to make the XML valid.