[1] Kriyakramakari ('Operational Techniques'[2]), along with Yuktibhasa of Jyeshthadeva, is one of the main sources of information about the work and contributions of Sangamagrama Madhava, the founder of Kerala school of astronomy and mathematics.
[3] Also the quotations given in this treatise throw much light on the contributions of several mathematicians and astronomers who had flourished in an earlier era.
Narayana (c. 1540–1610), the second author, was a Namputiri Brahmin belonging to the Mahishamangalam family in Puruvanagrama (Peruvanam in modern-day Thrissur District in Kerala).
Sarma's critical edition of Lilavati[5] based on Kriyakramakari, stanza 199 of Lilavati reads as follows[6] (Harvard-Kyoto convention is used for the transcription of the Indian characters): This could be translated as follows; Taking this verse as a starting point and commenting on it, Sanakara Variar in his Kriyakrakari explicated the full details of the contributions of Sangamagrama Madhava towards obtaining accurate values of π. Sankara Variar commented like this: Sankara Variar then cites a set of four verses by Madhava that prescribe a geometric method for computing the value of the circumference of a circle.
This technique involves calculating the perimeters of successive regular circumscribed polygons, beginning with a square.