Selection Group property / set property

hourigan

I just want to confirm what I think I am observing with commands in the python console.

Objective: I would like to record a property - say a weighted mean 207 Corrected Pb206/Pb238 age (and uncertainty) to the properties of a selection group. This will be useful for storing the ages of secondary standards and then accessing them for adding to the footers of data tables.

grp = data.selectionGroup('Z_FCT')

I can't get these to work

grp.property('No. of Selections")
grp.setProperty("Pb7c68Age". 28.4)

I can get these to work

grp.selection(0).property("Duration (s)")
grp.selection(0).setProperty("Pb7c68Age". 28.4)

This leads me to believe that the API doesn't allow group-level property access. The absence of these in the API write-up would suggest that too. I suppose this is a protection against accidentally overwriting a selection property at the group level. The reason to store it as a property is that a weighted mean age might have rejected outliers and therefore differ from the group result.

Age638 = data.groupResult(grp,data.timeSeries(‘Final Pb206/U238 age’)).mean()

This works:

grp = data.selectionGroup('DROM')
for s in grp.selections():
	s.setProperty("Pb7c638Age", 28.4) 

Pb7c638Age = grp.selection(0).property("Pb7c638Age")

A function might help add the age and uncertainty (global to all selections in group) as well the outlier status (specific to the selection)

def addAgeProperty (group, propDesc, value, unc, outlier)
	grp = data.selectionGroup(group)
	for idx, s in enumerate(grp.selections()):
		s.setProperty(f"Group {propDesc}",value)
		s.setProperty(f"Group {propDesc} unc",unc)
		s.setProperty(f"Group {propDesc} outlier",outlier[idx])

Or perhaps more generic:

def addGroupProperty (group, propDesc, value)
	grp = data.selectionGroup(group)
	if len(value) > 1:
        	for idx, s in enumerate(grp.selections()):
			s.setProperty(f"Group {propDesc}",value[idx])
	else:
		for s in grp.selections():
			s.setProperty(f"Group {propDesc}",value)

Joe

hourigan

There are a few different things going on here:

Properties of groups and selections come in two varieties: a "built-in" type and a dynamic type. The built-in properties, like name, type, number of selections etc., cannot be retrieved with .property(...), instead you use group.name, group.type, group.count, etc. for these.
From python doing group.setProperty(...) sets a property on the underlying C++ object (which is what we want), but doing group.property(...) in python gets the property on the python wrapper of that C++ object. The two are not the same, so you get nothing back. This is not by design and is a bug. I've fixed that now. Note that these dynamic group properties will not show up in the group properties table (for the time being). This table shows the built-in group properties and a summary of the group's selection properties.
There is already group.setPropertyOnSelections(name, value), but this sets the same property for all of the group selections.
I've just added group.setPropertiesOnSelections(name, values). In this case, values should be a list of values where the length is the same as the number of selections.
Your addGroupProperty function will do the trick most of the time, but watch out for value being a string (which will have len > 1), and cases where the len of value is < number of selections.

All the best,