Ogs6py doesn't replace text when Medium ID defined

Usability
1

Problem Definition

I am extensively using the feature replaceTxt of ogs6py in order to adapt existing .prj files.
Usually, the command replaceMediumProperty is sufficient to replace constant medium parameters.
Well, for changing a linear dependent parameter definition one needs the command replaceText. Unfortunately, replaceTxt does not work for me being assigned to a certain medium with a specific medium id. At least I couldn’t make it until now…

Example

model_example=OGS(INPUT_FILE="example.prj", PROJECT_FILE="example.prj")
slope = 6.0463e-10

I want to change the value of slope in example.prj

 <media>
        <medium id="0">
            <phases>
                <phase>
                    <type>Gas</type>
                    <properties>
                        <property>
                            <name>viscosity</name>
                            <type>Linear</type>
                            <independent_variable>
                                <variable_name>phase_pressure</variable_name>
                                <reference_condition>0</reference_condition>
                                <slope>6.046e-10</slope>
                            </independent_variable>

by using:

 model_example.replaceTxt(slope,xpath="./media/medium[id='0']/phases/phase[type='Gas']/properties/property[name='viscosity']/independent_variable/slope")
 model_example.writeInput()

Python executes but doesn’t change the Parameter in .prj file.
At the same time, the following command works but can not be assigned to a certain medium id:

model_example.replaceTxt(slope,xpath="./media/medium/phases/phase[type='Gas']/properties/property[name='viscosity']/independent_variable/slope")

@joergbuchwald , you might have any idea what I might have done wrong?

Thank you very for your help in advance and thanks for this all in all really great tool ogs6py. :rocket: :slightly_smiling_face:

Best regards
Linus

2

Hi @Linusvagabund
as id is an attribute it needs to be addressed differently:

xpath="./media/medium[@id='0']/phases/phase[type='Gas']/properties/property[name='viscosity']/independent_variable/slope"

alternatively, you can also use the occurrence keyword to denote that you want to change only the zeroth occurrence:

model_example.replaceTxt(slope,xpath="./media/medium/phases/phase[type='Gas']/properties/property[name='viscosity']/independent_variable/slope", occurrence=0)
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