search for: 999th

...nto 999 groups of 564 rows and output each group as a CSV files... Obviously I could do this longhand but I know it is somehow possible to write a loop to do the same thing... I'd like to group such that the first group is the first 564 rows, the second group is the second 564 rows ..... the 999th group is the 999th 564 rows... In each newly created group, I'd like there to be a new column that identifies the group... i.e. the first group would have a new column in which all 564 observations have a character value of "group1" Finally I'd also like to output each one of t...