The introduction of multi-format headers to SEPlib is one of the key components of SEP90. It is also one of the most difficult parts of the SEP90 data structure to effectively incorporate into Fortran77. With our Fortran90 library, multiple data formats do not cause a problem. Our structure independently holds the two data formats currently supported by SEP90, integer and reals, and uses the key type structure to navigate the rhdr and ihdr routines.
| Name | Type | Description |
| sepdata | sep_type | The name of dataset. |
| key_num | integer | Key index or |
| key_name | character (len=*) | The key name. |
| index2..7 | integer | Location with in sep_hdr array. |
To the user, accessing header routines is straight-forward. The user can either access header information through the key index or by the key name. To access the header in a 4-D data set the call would be simply.
header(sepdata,key_num,i2,i3,i4)
or
header(sepdata,"sx",i2,i3,i4)