An attribute is a flag array associated with the grid functions. For instance, an attribute may tell which grid functions are to be output and which are not. Attributes are defined in a similar manner to vector parameters, except the size is replaced by an encoding. The encoding is either encodeone or encodeall, with encodeone giving one value per grid function and encodeall giving one value per time level per grid function. For instance, if five grid functions are defined, three of which have three time levels each while the remaining two have two levels each, then an attribute marked as encodeone would have a length of five, while an attribute marked as encodeall would have a length of thirteen. In this case an output flag array could be defined as either
attribute int out_gf encodeone
or
attribute int out_gf encodeone := [0 0 1 1 0]