ततो॑ वि॒राड॑जायत वि॒राजो॒ अधि॒ पूरु॑षः । स जा॒तो अत्य॑रिच्यत प॒श्चाद्भूमि॒मथो॑ पु॒रः ।। ५ ।।
From him Virâj was born; again Purusha from Virâj was
born.
When born, he spread to west and east beyond the boundaries
of earth.
Ralph T. H. Griffith
The surface that matched
Both passages fold to the same comparison surface. Accents, word breaks and sandhi are removed before comparison, so this string is not how either text reads.
ततो विराडजायत विराजो अधि पूरुषः स जातो अत्यरिच्यत पश्चाद्भूमिमथो पुरः
These links are derived by comparing normalised Sanskrit surfaces. They show that two collections carry the same wording. They are not, by themselves, a demonstrated line of transmission between them, and the direction stored on an edge is a property of how it was built.
Samaveda is one of four collections held here. Cross-corpus comparison bottoms out at the weakest shared surface, because a Devanagari text and a romanised text share no code points.
How these were derived1
Parallelism is symmetric and this graph stores it as a directed edge, so these relations are traversed in both directions and each row states which way the stored edge ran. All 1,684 REUSES_TEXT_FROM edges point Samaveda-to-Rigveda, and 1,421 Rigvedic passages have reuse edges only inbound; following the arrow would show those 1,421 verses no reuse at all.