Helper function for the calculation of sequence coverage, replaces identified positions with an "x" within the protein sequence.

replace_identified_by_x(sequence, positions_start, positions_end)

## Arguments

sequence a character value that contains the protein sequence. a numeric vector of start positions of the identified peptides. a numeric vector of end positions of the identified peptides.

## Value

A character vector that contains the modified protein sequence with each identified position replaced by "x".