New aggregate function for extreme values (positive / negative)

[ManniHRath]

Hi there !
I'm new with HA und mini graph card but very pleased about it. I now want to build up a graph based on data which will contain positive an negative values as well. I would like to use an aggregate function that takes the most extreme value: The biggest if there is a positive value within the aggregated data and the smallest (most negative) if all values are negative. Does the aggregate func 'max' work like this? If not: I suggest to implement such an aggregate func (maybe call it 'extreme') ?