Using spare columns

You can use spare columns in the C array for data manipulation and storing additional information. However, it might be clearer to store this information in named variables where the name gives some indication of the type of data stored.

In ordinary records you can use the space beyond the end of the record. If the record length is 120 columns, you can use columns 121 to 1000.

Note For ordinary records, only columns 1 to reclen are reset to blanks, where reclen is the maximum record length as defined by the reclen= keyword on the struct statement. For more information about defining the record length, see Record length.

In multicard records you can not use c(1,100). However, you can use any columns between the end of the card (reclen) and the end of that row of the C array. For example, when reclen=80 you can use c(181,200), c(281,300) and so on. You can also use full sets of columns in which there is no data: that is, if the record has only four cards (1, 2, 3 and 4), then c(501,1000) are the spare columns you can use. Additionally, cells 101 to c(100+reclen), c201 to c(200+reclen), and so on are reset to blanks before the next record is read in.