Develop Reference

How can I extract elementary values with ElementTree in Python?

I try to extract values attributes (ex. 'Filename') of that XML file in Python.
Can you help me ?
Here is the MC 'Librarytest.xml' file :
<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<MPL Version="2.0" Title="Library">
<Item>
<Field Name="Filename">Y:\Styx\08 - Styx - Snowblind8. Snowblind.flac</Field>
<Field Name="Name">Snowblind</Field>
<Field Name="Artist">Styx</Field>
<Field Name="Album">Paradise Theater</Field>
<Field Name="Genre">Rock</Field>
</Item>
<Item>
<Field Name="Filename">Y:\David Gilmour\04 A Boat Lies Waiting.flac</Field>
<Field Name="Name">A Boat Lies Waiting</Field>
<Field Name="Artist">David Gilmour</Field>
<Field Name="Album">Rattle That Lock (Deluxe)</Field>
<Field Name="Genre">Progressive</Field>
</Item>
</MPL>
I try this :
import xml.etree.ElementTree as ET
xml_file = 'C:/Users/ClientMD/Downloads/MC Librarytest.xml'
tree = ET.parse(xml_file)
root = tree.getroot()
for each in root.findall('.//Field'):
rating = each.find('.//Filename')
print ('Nothing' if rating is None else rating.text)
and I obtain :
Nothing
...
Nothing

Like this:
import xml.etree.ElementTree as ET
xml_file = 'C:/Users/ClientMD/Downloads/MC Librarytest.xml'
tree = ET.parse(xml_file)
root = tree.getroot()
for each in root.findall('.//Field[#Name="Filename"]'):
rating = each.text
print ('Nothing' if rating is None else rating)
Output
Y:\Styx\08 - Styx - Snowblind8. Snowblind.flac
Y:\David Gilmour\04 A Boat Lies Waiting.flac

If you want to grab more elements and keep them under a single item context - you can use the below
import xml.etree.ElementTree as ET
xml = '''<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<MPL Version="2.0" Title="Library">
<Item>
<Field Name="Filename">Y:\Styx\\08 - Styx - Snowblind8. Snowblind.flac</Field>
<Field Name="Name">Snowblind</Field>
<Field Name="Artist">Styx</Field>
<Field Name="Album">Paradise Theater</Field>
<Field Name="Genre">Rock</Field>
</Item>
<Item>
<Field Name="Filename">Y:\David Gilmour\\04 A Boat Lies Waiting.flac</Field>
<Field Name="Name">A Boat Lies Waiting</Field>
<Field Name="Artist">David Gilmour</Field>
<Field Name="Album">Rattle That Lock (Deluxe)</Field>
<Field Name="Genre">Progressive</Field>
</Item>
</MPL>'''
INTERESTING_NAMES = ['Filename','Artist']
data = []
root = ET.fromstring(xml)
for item in root.findall('.//Item'):
temp = {}
for name in INTERESTING_NAMES:
temp[name] = item.find(f'Field[#Name="{name}"]').text
data.append(temp)
print(data)
output
[{'Filename': 'Y:\\Styx\\08 - Styx - Snowblind8. Snowblind.flac', 'Artist': 'Styx'}, {'Filename': 'Y:\\David Gilmour\\04 A Boat Lies Waiting.flac', 'Artist': 'David Gilmour'}]

xml.etree.ElementTree access subelement without creating

I have a code
ffdata = ET.Element("FFData")
fForm = ET.SubElement(ffdata, "Form")
fForm.set("FormDefId","{DD0F88DD-A858-4595-AF2F-3643D0069A39}")
fPages = ET.SubElement(fForm, "Pages")
for xml_file in xml_files:
xml_file = os.path.join(*[CurrentFolderPath,xml_file])
tree = ET.parse(xml_file)
xml_data = tree.getroot()
for xPage in xml_data.iter('Page'):
# --- Ignore first element
if int(xPage.attrib['PageNumber']) >1:
#---- Change Paginators index
xPage.set('PageNumber',str(sPageNumber))
# -- Set page number to fields
fFields = ET.SubElement(xPage, "Fields")
fxField = ET.SubElement(fFields, "Field")
fxField.set('PageNumber',str(sPageNumber-1))
fPages.append(xPage) # Add element to root
sPageNumber= sPageNumber +1
else:
if sImoneExists == 0:
fPages.append(xPage) # Add element to root
sImoneExists = 1
fPages.set("Count",str(sPageNumber-1))
indent(ffdata)
tree = ET.ElementTree(ffdata)
xml_file_save = os.path.join(*[CurrentFolderPath,"Merged.ffdata"])
tree.write(xml_file_save)
i trying to change sub element inside loop
fFields = ET.SubElement(xPage, "Fields")
fxField = ET.SubElement(fFields, "Field")
fxField.set('PageNumber',str(sPageNumber-1))
But it create new element instead of change existing
so i get
<FFData>
<Form FormDefId="{DD0F88DD-A858-4595-AF2F-3643D0069A39}">
<Pages Count="41">
<Page PageDefName="1" PageNumber="2">
<Fields Count="135">
<Field Name="L1-1"></Field>
<Field Name="PageNumber">1</Field>
</Fields>
<Fields>
<Field PageNumber="2" />
</Fields>
</Page>
</Pages>
</Form>
</FFData>
expected
<FFData>
<Form FormDefId="{DD0F88DD-A858-4595-AF2F-3643D0069A39}">
<Pages Count="41">
<Page PageDefName="1" PageNumber="2">
<Fields Count="135">
<Field Name="L1-1"></Field>
<Field Name="PageNumber">2</Field>
</Fields>
</Page>
</Pages>
</Form>
</FFData>
So how to change existing sub element of each iterating page?

Converting pandas dataframe to XML

I know this question has been asked before and my last was put on hold, so now I'm specifying it detailed.
I have a CSV file of population information, I read it to pandas and now have to transform it to XML, for example like this
<?xml version="1.0" encoding="utf-8"?>
<populationdata>
<municipality>
<name>
Akaa
</name>
<year>
2014
</year>
<total>
17052
......
This is the reading part of my code:
import pandas as pd
pop = pd.read_csv(r'''directory\population.csv''', delimiter=";")
Tried doing it like in mentioned before in the link here with function and cycle: How do convert a pandas/dataframe to XML?. Haven't succeeded, any other recommendations maybe?
This is an example of my dataframe:
Alahärmä 2014 0 0.1 0.2
0 Alajärvi 2014 10171 5102 5069
1 Alastaro 2014 0 0 0
2 Alavieska 2014 2687 1400 1287
3 Alavus 2014 12103 6102 6001
4 Anjalankoski 2014 0 0 0
Fairly new to python, so any help is apreciated.

The question you have linked to actually has a great answer to your question but I guess you’re having difficulty transposing your data into that solution so Ive done it below for you.
Ok your level of detail is a bit sketchy. If your specific situation differs slightly then you'll need to tweak my answer but heres something that works for me:
First off assuming you have a text file as follows :
0 Alahärmä 2014 0 0.1 0.2
1 Alajärvi 2014 10171 5102 5069
2 Alastaro 2014 0 0 0
3 Alavieska 2014 2687 1400 1287
4 Alavus 2014 12103 6102 6001
5 Anjalankoski 2014 0 0 0
Moving on to creating the python script, we first import that text file using the following line:
pop = pd.read_csv(r'directory\population.csv', delimiter=r"\s+", names=['cityname', 'year', 'total', 'male', 'females'])
This brings in the text file as a dataframe and gives the new dataframe the correct column headers.
Then taking the data from the question you linked to, we add the following to our python script:
def func(row):
xml = ['<item>']
for field in row.index:
xml.append(' <field name="{0}">{1}</field>'.format(field, row[field]))
xml.append('</item>')
return '\n'.join(xml)
print('\n'.join(pop.apply(func, axis=1)))
Now we put it all together and we get the below:
import pandas as pd
pop = pd.read_csv(r'directory\population.csv', delimiter=r"\s+", names=['cityname', 'year', 'total', 'male', ‘females'])
def func(row):
xml = ['<item>']
for field in row.index:
xml.append(' <field name="{0}">{1}</field>'.format(field, row[field]))
xml.append('</item>')
return '\n'.join(xml)
print('\n'.join(pop.apply(func, axis=1)))
When we run the above file we get the following output:
<item>
<field name="cityname">Alahärmä</field>
<field name="year">2014</field>
<field name="total">0</field>
<field name="male">0.1</field>
<field name="females">0.2</field>
</item>
<item>
<field name="cityname">Alajärvi</field>
<field name="year">2014</field>
<field name="total">10171</field>
<field name="male">5102.0</field>
<field name="females">5069.0</field>
</item>
<item>
<field name="cityname">Alastaro</field>
<field name="year">2014</field>
<field name="total">0</field>
<field name="male">0.0</field>
<field name="females">0.0</field>
</item>
<item>
<field name="cityname">Alavieska</field>
<field name="year">2014</field>
<field name="total">2687</field>
<field name="male">1400.0</field>
<field name="females">1287.0</field>
</item>
<item>
<field name="cityname">Alavus</field>
<field name="year">2014</field>
<field name="total">12103</field>
<field name="male">6102.0</field>
<field name="females">6001.0</field>
</item>
<item>
<field name="cityname">Anjalankoski</field>
<field name="year">2014</field>
<field name="total">0</field>
<field name="male">0.0</field>
<field name="females">0.0</field>
</item>

Parsing name/value pairs from XML

I am trying to pull account details from XML files supplied by vendors.
I have one vendor that supplied XML files like:
<Accounts>
<Account>
<AccountNumber>1234567</AccountNumber>
<Balance>$200.00</Balance>
</Account>
<Account>
...
</Account>
</Accounts>
And I can parse this fairly easily using python:
mytree = et.parse(xml_path)
myroot = mytree.getroot()
for acc in charges_root.findall('Account'):
acctnum = acc.find('AccountNumber').text
balance = acc.find('Balance').text
print(acctnum, balance)
Which outputs like this:
1234567 $200.00
However another vendor supplies the XML files in something more like name/value pairs, and I am unsure how to easily access that data. It doesn't work the same way as above:
<Accounts>
<Account>
<field name='AccountNumber' value='1234567' />
<field name='Balance' value='$200.00' />
</Account>
<Account>
...
</Account>
</Accounts>
So far I've got this, but would like to be able to access the values separately and easily:
mytree = et.parse(xml_path)
myroot = mytree.getroot()
for field in myroot.findall('Account'):
for line in field:
print(line.attrib)
Which outputs something like:
{'name': 'AccountNumber', 'value': '1234567'}
{'name': 'Balance', 'value': '$200.00'}
So my question is this - How can I access the values and assign them to variables (based on the name) so that I can make use of them elsewhere in the script, like I have with acctnum and balance in the first example?

Populate a new datastructure (like a dict) from the field when you iterate instead of just discarding:
account_d = {}
for field in myroot.findall('Account'):
for line in field:
account_d[line.attrib['name']] = line.attrib['value']
# account_d should now be:
# { 'AccountNumber': '1234567', 'Balance': '$200.00' }
You can use a list of lists/tuples too:
account_a = []
for field in myroot.findall('Account'):
for line in field:
account_d.append(line.attrib['name'], line.attrib['value'])
# account_a should now be:
# [('AccountNumber', '1234567'), ('Balance', '$200.00')]

ElementTree 1.3 has the ability to locate nodes with particular attributes:
from xml.etree import ElementTree as et
data = '''\
<Accounts>
<Account>
<field name='AccountNumber' value='1234567' />
<field name='Balance' value='$200.00' />
</Account>
<Account>
<field name='AccountNumber' value='9999999' />
<field name='Balance' value='$300.00' />
</Account>
</Accounts>'''
tree = et.fromstring(data)
for acc in tree.iterfind('Account'):
acctnum = acc.find("field[#name='AccountNumber']").attrib['value']
balance = acc.find("field[#name='Balance']").attrib['value']
print(acctnum,balance)
1234567 $200.00
9999999 $300.00

You can do it by collecting all the Account element's field attributes into a dictionary and then using the information in it as needed:
accounts.xml sample input file:
<?xml version="1.0"?>
<Accounts>
<Account>
<field name='AccountNumber' value='1234567' />
<field name='Balance' value='$200.00' />
</Account>
<Account>
<field name='AccountNumber' value='8901234' />
<field name='Balance' value='$100.00' />
</Account>
</Accounts>
Code:
import xml.etree.ElementTree as et
xml_path = 'accounts.xml'
mytree = et.parse(xml_path)
myroot = mytree.getroot()
for acct in myroot.findall('Account'):
info = {field.attrib['name']: field.attrib['value']
for field in acct.findall('field')}
acctnum, balance = info['AccountNumber'], info['Balance']
print(acctnum, balance)
Result:
1234567 $200.00
8901234 $100.00

Question: How can I access the values and assign them to variables (based on the name)
Convert all Accounts to a Dict[AccountNumber] of Dict[field].
The Attribute name becomes the dict Key:
Accounts = {}
for account in root.findall('Account'):
fields = {}
for field in account.findall('field'):
fields[field.attrib['name']] = field.attrib['value']
print('{a[AccountNumber]} {a[Balance]}'.format(a=fields))
Accounts[fields['AccountNumber']] = fields
print(Accounts)
Output:
1234567 $200.00
9999999 $300.00
{'9999999': {'AccountNumber': '9999999', 'Balance': '$300.00'}, '1234567': {'AccountNumber': '1234567', 'Balance': '$200.00'}}
Tested with Python: 3.4.2

How can I display the child element of a node from an xml file, in python?

Here is my xml file
<root>
<Module name="ac4" offset="32" width="12">
<register name="xga_control" offset="0x000" width="32" access="R/W">
<field name="reserved" offset="0" bit_span="5"/>
<field name="force_all_fault_clear" bit_span="1" default="0">
<description>Rising edge forces all fault registers to clear</description>
</field>
<field name="force_warning" default="0" bit_span="1">
<description>Forces AC2 to report a Master Warning</description>
</field>
<field name="force_error" default="0" bit_span="1">
<description>Forces AC2 to report a Master Error</description>
</field>
</register>
</Module>
<root>
Right now I can access the names of my registers and display them. However I also want to display the names and attributes of my field elements. How can I do that? Here is my code so far.
input_file = etree.parse('file1.xml')
output=open("ac4.vhd","w+")
output.write("Registers \n")
for node in input_file.iter():
if node.tag=="register":
name=node.attrib.get("name")
print(name)
output.write(name)
output.write("\n")
if node.tag=="field":
name=node.attrib.get("name")
output.write(name)
Right now the output looks like
Registers
xga_control
i_cmd_reg
I want it to look like
Registers
xga_control
reserved
force_all_fault_clear
force_warning
force_error
i_cmd_reg
field name
field name
Any ideas on how to do this?

Instead of iterating over input_file.iter() you can do input_file.getroot() and iterate systematically over that.
This is how you would write your code:
import xml.etree.ElementTree as ET
tree = ET.parse('file1.xml')
root = tree.getroot()
with open('ac4.vhd', 'w+') as fd:
fd.write('Registers\n')
for node in root:
if node.tag == 'Module':
for sub_node in node:
fd.write('{0}\n'.format(sub_node.get('name')))
for child in sub_node:
fd.write('\t{0}\n'.format(child.get('name')))
Your output becomes:
Registers
xga_control
reserved
force_all_fault_clear
force_warning
force_error