I want to assign various properties to objects and then select all objects with a certain set of values for those properties.
The objects are graphs from tests (created with CSV Mesh Importer, so they are lines, not solids). They all have a value for, for example, length and width (not of the Blender object but of the object the test was done on). I want to then select all objects that have, say, length 5.3 and width 3.8.
I already found that I can group objects and then select the grouped objects. But for that I have to select one of the objects first. But I want to select the properties, and a set of them, and then select all objects that share that set of properties.
I also found Custom Properties, but I can't figure out how that works, and most explanations use Python, but I want to do it in the GUI. Also, I want to set the properties just once, and that is not what it seems to be meant for.