create a new column with t_vaf score and filter by it

[MjelleLab]

t_vaf is not included in my merged mag object, so I wanted to calculate it using the formula below. However, the column that is being created is not recognised by for instance subsetMAF afterwards. How do I create a valid column that I can use for filtering t_vaf? In the end I want to remove rows with var below a certain threshold.

The t_vaf column is not recognised a a new valid column: laml.mafs@data$t_vaf <- as.numeric(laml.mafs@data$t_alt_count/(laml.mafs@data$t_alt_count+laml.mafs@data$t_ref_count))