IfcOpenShell, how to add a new property and value to an object?

M by Moult on 19 Aug 2022 #

@InformationWorker if you are getting errors like that, it suggests there is something fundamentally broken with your installation of IfcOpenshell. For example, does this code work for you?


import ifcopenshell

f = ifcopenshell.file()

f.create_entity('IfcPerson')

If not, try uninstall your IfcOpenShell and reinstall following the instructions here: https://blenderbim.org/docs-python/ifcopenshell-python/installation.html - also feel free to reach out for live help at https://osarch.org/chat where we can screenshare and solve it together.

C by Coen on 20 Apr 2023 #

How would I add an IfcWall to an existing IFC using the ifcopenshell.api? I could only find in the documentation how to create an entire IFC from scratch.

C by cvillagrasa on 20 Apr 2023 # +1 votes

I believe that just like this:


import ifcopenshell

model = ifcopenshell.open('/path/to/your/model.ifc')

wall = ifcopenshell.api.run('root.create_entity', model, ifc_class='IfcWall', predefined_type='SOLIDWALL')

Have you had a look at the base ifcopenshell-python docs (not the API)?

B by bernd on 21 Apr 2023, edited 21 Apr 2023 # +1 votes

https://github.com/IfcOpenShell/IfcOpenShell/blob/v0.7.0/src/blenderbim/scripts/obj2ifc.py

line 76 - 83 does add the new object, add it to the spatial tree and sets the placement. Before line 76 the geometry is created

C by Coen on 26 Apr 2023 #

How does one delete an entire PropertySet?

M by Moult on 26 Apr 2023 # +1 votes

@Coen use the pset.remove_pset api. https://blenderbim.org/docs-python/autoapi/ifcopenshell/api/pset/remove_pset/index.html

G by glavoc on 8 Jun 2023, edited 8 Jun 2023 #

Hi,

@Moult said:

In IFC, attributes are fixed. If you want to add arbitrary properties, use property sets, not attributes. This is as @Coen has explained. However, there is a simpler method using the IfcOpenShell API.

import ifcopenshell

import ifcopenshell.api

ifc = ifcopenshell.open('path\to_your\ifc_file')

element = ifc.by_type("IfcElement")[0] # Just as an example, you will need to select the elements you want to add properties to yourself.

pset = ifcopenshell.api.run("pset.add_pset", ifc, product=element, name="Your Property Set Name")

ifcopenshell.api.run("pset.edit_pset", ifc, pset=pset, properties={"foo": "foobar", "foo2": "foobaz"})

this code is not working for me, I don't have much experience with ifc.

Im trying to assign parameters coming from excel file.


f = ifcopenshell.open(ifc_path)

df = pd.read_excel(xls_path), sheet_name="CONCRETE")

for index, row in df.iterrows():

    ifcguid = row['IfcGUID']

    el = f.by_id(ifcguid) 

    pset = ifcopenshell.api.run("pset.add_pset", f, product=el, name="Pset_AsBuilt")

    ifcopenshell.api.run("pset.edit_pset", f, pset=pset, properties=row)

f.write(ifc_path)

and it looks like they do get assigned to elements but they are not visible in bim viewer/blender.

this is ifc file after editing. for example:


#1069189=IFCPROPERTYSINGLEVALUE('Product Manufacture Name',$,IFCLABEL('40MPa Aquron'),$);

#1069176=IFCPROPERTYSET('1KvRowVMrEIfpEJA8$4jLm',#1069175,'Pset_AsBuilt',$,(#1069179,#1069180,#1069181,#1069182,#1069183,#1069184,#1069185,#1069186,#1069187,#1069188,#1069189,#1069190,#1069191));

#1069177=IFCOWNERHISTORY(#192,#188,.READWRITE.,.ADDED.,1686207125,#192,#188,1686207125);

#1069178=IFCRELDEFINESBYPROPERTIES('3S7ICTkE9BIBEDyYqYj8K7',#1069177,$,$,(#8997),#1069176);

#8997=IFCSLAB('0e3zm5Y85BhfXSflZpYTEV',#193,'Default Slab','1,..\\..\\..\\..\\.......................