Change the value of a parameter in xml file using matlab

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I have xml file and want to change a value of a parameter inside it. The line that has that specific parameter is:
<variable id="MIG" value="3" description="Change in MIG" />
I want to change value from 3 to other number.
I found these functions to read and write xml file:
DOMnode = xmlread('parameter.xml');
xmlwrite('newparameter.xml',DOMnode);
but not sure how to change the value of variable called "MIG".

Answers (2)

Abhilash Padma
Abhilash Padma on 1 Oct 2019
To change the value of a parameter in an element, along with xmlread and xmlwrite, we need to use getElementsByTagName and setAttribute methods. See the following code where I have changed the value of parameter “value”.
test.xml
<variable id="MIG" value="3" description="Change in MIG" />
xDoc=xmlread(fullfile(('test.xml')));
allListItems=xDoc.getElementsByTagName('variable');
thisListItem=allListItems.item(0);
thisListItem.setAttribute('value','20');

Robert Ungi
Robert Ungi on 3 Jan 2022
A more general way to do so is
% <?xml version="1.0" encoding="utf-8"?>
% <xml>
% <busStop endPos="30" id="BusStop0" lane="1to2_0" startPos="20"/>
% <busStop endPos="80" id="BusStop1" lane="1to2_0" startPos="70"/>
% <chargingStation chrgPower="220" endPos="30" id="ChrgStn1" lane="1to2_0" startPos="45"/>
% </xml>
import javax.xml.xpath.*
factory = XPathFactory.newInstance;
import javax.script.ScriptContext;
xpath = factory.newXPath;
fXML=xmlread('SampleXML.xml');
expression = xpath.compile('xml/chargingStation[@id="ChrgStn1"]');
chargingStation = expression.evaluate(fXML, XPathConstants.NODESET);
for i=0:chargingStation.getLength-1
chargingStation.item(i).setAttribute('startPos', "45")
end
xmlwrite('SampleXMLOut.xml', fXML);
Adopted from The Wizzart.

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