Trend calculation for selected time steps #37
Description
Currently the distinction between earlier and later sum is fixed on the half of all time steps regardless if they are selected. Then, the selected time steps of each half are summed.
Idea for an alternative calculation of trend depending on selected time steps:
- 1 time step selected -> no calculation and show an "!" icon in the column (onHover a tooltip explains that more than 1 quarter needs to be selected)
- even number of quarters selected -> calculate difference between sum of earlier half and later half (even if there is a gap by some unselected time steps)
- odd number of quarters selected -> different ideas:
- either ignore middle quarter (and calculate like for even number),
- split middle quarter between the halves (same as above but with larger divisor), or
- make no calculation (like for 1 time step selected)
See also discussion in #32.