Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

Objective: Calculate the expanding mean of the ‘valuation’ column for each ‘slug’ group, excluding the current row’s value (and respecting ordering i.e. ‘week’).

I have a dataframe containing columns with groups of 1’s and -1’s. Each column could contain any amount of 1’s or -1’s grouped together within each column, and they could also begin with an unspecified number of NaN’s. I would like to count the total of values within each group excluding the NaN’s.

I have a class for movies: