delsetSynopsissub: void delset(set) sub: eset delset(eset, set) DescriptionThe delset command, in its first form, deletes from all relations (esets) in the currently loaded factbase tuples that either begin or end with one of the members of the provided set. In its second form, the operation is only performed on the eset provided as the first parameter. The original relation remains unchanged; instead, the result of the deletion is returned by delset.ExampleIn this example a relation called someRel is created. The first call to delset is applied to only that one relation, with instructions to delete edges that begin or end with either the word "come" or the number 4. The result is returned by delset, with someRel itself remaining unaffected. The second call to delset instructs it to remove tuples beginning or ending in the word "together' or the number 1. We can see the effects of this command by printing out the someRel relation.
>> words={"come", "together", "right", "now"}
>> numbers={1,2,3,4}
>> someRel = words X numbers
>> someRel
come 4
come 2
come 1
come 3
together 4
together 2
together 1
together 3
right 4
right 2
right 1
right 3
now 4
now 2
now 1
now 3
>> delset (someRel, {"come", 4})
together 2
together 1
together 3
right 2
right 1
right 3
now 2
now 1
now 3
>> delset ({"together", 1})
>> someRel
come 4
come 2
come 3
right 4
right 2
right 3
now 4
now 2
now 3
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