Sine table in ancient India

Abstract

The construction of jya̅table (or Indian sine table) was given great importance by Indian astronomers from fourth century A.D. onwards as it was required to calculate the planetary positions as accurately as possible. Technique of constructing the table has been described here as their probable method of computation. Greek Ptolemy (A.D. 150) gave previously similar sine table. This was further developed into tangent and co-tangent tables by the Arabs. The paper also contains a discussion on the priority or otherwise of the Indian and Greek origin of the sine table.