align                   Align a 'data.table' onto a 'nanotime' vector
align_idx               Get the index of the alignment of one vector
                        onto another
frequency,data.table-method
                        Return the number of observations per interval
grid_align              Align a 'data.table' onto a 'nanotime' vector
                        grid
ops                     Arithmetic operations on two 'data.table'
                        time-series
