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- 1. Introduction Aryabhata Brahmagupta Bhaskara I Madhava References On Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 2. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesOutline 1 Introduction 2 Aryabhata’s diﬀerence table 3 Brahmagupta’s interpolation formula 4 Bhaskara I’s approximation formula 5 Madhava’s power series expansions 6 ReferencesV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 3. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesIntroduction IntroductionV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 4. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesObjectives To present some of the greatest achievements of pre-modern Indian mathematicians as contributions to the development of numerical analysis.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 5. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMain themes We present four themes: 1 Diﬀerence tables 2 Interpolation formulas 3 Rational polynomial approximations 4 Power series expansionsV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 6. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabhata’s diﬀerence table Aryabhata’s diﬀerence tableV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 7. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabhata’s sine table Aryabhata I’s (476 - 550 CE) celebrated work Aryabhatiyam contains a sine table. Aryabhata’s table was the ﬁrst sine table ever constructed in the history of mathematics. The tables of Hipparchus (c.190 BC - c.120 BC), Menelaus (c.70 - 140 CE) and Ptolemy (c.AD 90 - c.168) were all tables of chords and not of half-chords.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 8. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesWhat Aryabhata tabulated Aryabhata tabulated the values of jya (measured in minutes) for arc equal to 225 minutes, 450 minutes, ... , 5400 minutes. (Twenty-four values.)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 9. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesWhat others tabulated Pre-Aryabhata astronomers tabulated values of chords for various arcs.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 10. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabhata’s table The stanza specifying Aryabhata’s table is the tenth one (excluding two preliminary stanzas) in the ﬁrst section of Aryabhatiya titled Dasagitikasutra.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 11. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabhata’s table in his notation (Table values are encoded in a scheme invented by Aryabhata.)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 12. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabhata’s table in modern notation 225 224 222 219 215 210 205 199 191 183 174 164 154 143 131 119 106 93 79 65 51 37 22 7 (Read numbers row-wise.)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 13. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesInterpretation of Aryabhata’s table Aryabhata’s table is not a table of the values of jyas. Aryabhata’s table is a table of the ﬁrst diﬀerences of the values of jyas.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 14. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAryabahata’s table as a table of ﬁrst diﬀerences Angle (A) Value in A’bhata’s value Modern value (in minutes) A’bhata’s table of jya (A) of jya (A) 225 225 225 224.8560 450 224 449 448.7490 675 222 671 670.7205 900 219 890 889.8199 1125 215 1105 1105.1089 1350 210 1315 1315.6656 1575 205 1520 1520.5885 1800 199 1719 1719.0000 . . . . . . . . . . . . Values in second column are diﬀerences of values in third column.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 15. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahmagupata’s interpolation formula Brahmagupata’s interpolation formulaV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 16. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahmagupta Brahmagupta’s (598 - 668 CE) works contain Sanskrit verses describing a second order interpolation formula. The earliest such work is Dhyana-graha-adhikara, a treatise completed in early seventh century CE. Brahmagupta was the ﬁrst to invent and use an interpolation formula of the second order in the history of mathematics.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 17. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahmagupta’s verse (Earliest appearance: Dhyana-graha-adhikara, sloka 17)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 18. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesTranslation of Brahmagupta’s verse Multiply half the diﬀerence of the tabular diﬀerences crossed over and to be crossed over by the residual arc and divide by 900 minutes (= h). By the result (so obtained) increase or decrease half the sum of the same (two) diﬀerences, according as this (semi-sum) is less than or greater than the diﬀerence to be crossed over. We get the true functional diﬀerences to be crossed over. (Gupta, R.C.. “Second order interpolation in Indian mathematics upto the ﬁfteenth century”. Indian Journal of History of Science 4 (1 & 2): pp.86 - 98.)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 19. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahamagupta’s verse : Interpretation (notations) Consider a set of values of f (x) tabulated at equally spaced values of x: x x1 · · · xr xr +1 · · · xn f (x) f1 · · · fr fr +1 · · · fn Let Dj = fj − fj−1 . Let it be required to ﬁnd f (a) where xr < a < xr +1 . Let t = a − xr and h = xj − xj−1 .V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 20. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahamagupta’s verse : Interpretation True functional diﬀerence = Dr + Dr +1 t |Dr − Dr +1 | ± 2 h 2 Dr + Dr +1 according as is less than or greater than Dr +1 . 2 True functional diﬀerence = Dr + Dr +1 t Dr +1 − Dr + 2 h 2V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 21. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahamagupta’s verse : Interpretation The functional diﬀerence Dr +1 in the approximation formula t f (a) = f (xr ) + Dr +1 h is replaced by this true functional diﬀerence. The resulting approximation fromula is Brahmagupta’s interpolation formula.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 22. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBrahmagupta’s interpolation formula Brahmagupta’s interpolation formula: t Dr + Dr +1 t Dr +1 − Dr f (a) = f (xr ) + + h 2 h 2 This is the Stirlings interpolation formula truncated at the second order.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 23. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara I’s approximation formula Bhaskara I’s approximation formulaV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 24. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara I Bhaskara I (c.600 - c.680), a seventh century Indian mathematician (not the author of Lilavati). Mahabhaskariya, a treatise by Bhaskara I, contains a verse describing a rational polynomial approximation to sin x.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 25. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara’s verse (Mahabhaskariya, VII, 17 - 19)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 26. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara’s verse: Translation (Now) I brieﬂy state the rule (for ﬁnding the bhujaphala and the kotiphala, etc.) without making use of the Rsine-diﬀerences 225, etc. Subtract the degrees of a bhuja (or koti) from the degrees of a half circle (that is, 180 degrees). Then multiply the remainder by the degrees of the bhuja or koti and put down the result at two places. At one place subtract the result from 40500. By one-fourth of the remainder (thus obtained), divide the result at the other place as multiplied by the anthyaphala (that is, the epicyclic radius). Thus is obtained the entire bahuphala (or, kotiphala) for the sun, moon or the star-planets. So also are obtained the direct and inverse Rsines. (R.C. Gupta (1967). Bhaskara I’ approximation to sine. Indian Journal of HIstory of Science 2 (2)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 27. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara I’s approximation formula Let x be an angle measured in degrees. 4x(180 − x) sin x = 40500 − x(180 − x)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 28. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesBhaskara I’s approximation formula This is a rational polynomial approximation to sin x when angle x is expressed in degrees. It is not known how Bhaskara arrived at this formula.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 29. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesAccuracy of Bhaskara’s approximation formula The maximum absolute error in using the formula is around 0.0016.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 30. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series expansions Madhava’s power series expansionsV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 31. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesSangamagrama Madhava Madhava ﬂourished during c.1350 - c.1425. Madhava founded the so called Kerala School of Astronomy and Mathematics. Only a few minor works of Madhava have survived. There are copious references and tributes to Madhava in the works of his followers.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 32. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine in Madhava’s wordsV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 33. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine in English Multiply the arc by the square of itself (multiplication being repeated any number of times) and divide the result by the product of the squares of even numbers increased by that number and the square of the radius (the multiplication being repeated the same number of times). The arc and the results obtained from above are placed one above the other and are subtracted systematically one from its above. These together give jiva collected here as found in the expression beginning with vidwan etc. (A.K. Bag (1975). Madhava’s sine and cosine series. Indian Journal of History of Science 11 (1): pp.54-57.)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 34. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine in modern notations Let θ be the angle subtended at the center of a circle of radius r by an arc of length s. Then jiva ( = jya) of s is r sin θ. jiva = s s2 − s· (22 + 2)r 2 s2 s2 − s· 2 · (2 + 2)r 2 (42 + 4)r 2 s2 s2 s2 − s· 2 · 2 · 2 − ··· (2 + 2)r 2 (4 + 4)r 2 (6 + 6)r 2V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 35. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine : reformulation forcomputations Chose a circle the length of a quarter of which is C = 5400 minutes. Let R be the radius of such a circle. Choose Madhava’s value for π: π = 3.1415926536. The radius R can be computed as follows: R = 2 × 5400/π = 3437 minutes, 44 seconds, 48 sixtieths of a second.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 36. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine : reformulation forcomputations For an arc s of a circle of radius R: π 3 π 5 π 7 s 3 R 2 s 2 R 2 s 2 R 2 jiva = s− − − −· · · C 3! C 5! C 7! 3 5 11 R π2 R π2 R π 2 The ﬁve coeﬃcients , , ... , were 3! 5! 11! pre-computed to the desired degree of accuracy.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 37. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for sine : Computational scheme jiva = s− s 3 (2220 39 40 )− C s 2 (273 57 47 )− C s 2 (16 05 41 )− C s 2 (33 06 )− C s 2 (44 ) − CV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 38. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s sine tableV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 39. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s sine table The table is a set of numbers encoded in the katapayadi scheme. The table contains the values of jya (or, jiva) for arcs equal to 225 minutes, ... , 5400 minutes (twenty-four values). The values are correct up to seven decimal places. Madhava computed these values using the power series expansion of the sine function.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 40. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s method vs. modern algorithm Madhava formulated his result on the power series expansion as a computational algorithm. This algorithm anticipates many ideas used in the modern algorithm for computation of sine function. Details in next slide ...V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 41. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s method vs. modern algorithm The ﬁrst point is that Madhava’s method was indeed an algorithm! Madhava used an eleventh degree polynomial to compute sine. Madhava used Taylor series approximation. Modern algorithms use minmax polynomial of the same degree. Madhava pre-computed the coeﬃcients to the desired accuracy. Modern algorithms also do the same. Madhava essentially used Horner’s method for the eﬃcient computation of polynomials. Modern algorithms also use the same method.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 42. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesMadhava’s power series for cosine and arctangent functions Madhava had developed similar results for the computation of the cosine function and also the arctangent function. See references for details.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 43. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesReferences ReferencesV. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 44. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesReferences Walter Eugene Clark (1930). The Aryabhatiya of Aryabhata: An ancient Indian work on mathematics and astronomy. Chicago: The University of Chicago Press (p.19). Meijering, Erik (March 2002). “A Chronology of Interpolation From Ancient Astronomy to Modern Signal and Image Processing”. Proceedings of the IEEE 90 (3): 319 - 342. Gupta, R.C.. “Second order interpolation in Indian mathematics upto the ﬁfteenth century”. Indian Journal of History of Science 4 (1 & 2): 86 - 98. R.C. Gupta (1967). “Bhaskara I’ approximation to sine”. Indian Journal of HIstory of Science 2 (2)V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 45. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesReferences (continued) Bag, A.K. (1976). “Madhava’s sine and cosine series”. Indian Journal of History of Science (Indian National Academy of Science) 11 (1): 54 - 57. C.K. Raju (2007). Cultural foundations of mathematics: The nature of mathematical proof and the transmission of calculus from India to Europe in the 16 thc. CE. History of Philosophy, Science and Culture in Indian Civilization. X Part 4. Delhi: Centre for Studies in Civilizations. pp. 114 - 123. Kim Plofker (2009). Mathematics in India. Princeton: Princeton University Press. pp. 217 - 254. Joseph, George Gheverghese (2009). A Passage to Inﬁnity : Medieval Indian Mathematics from Kerala and Its Impact. Delhi: Sage Publications (Inda) Pvt. Ltd.V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics
- 46. Introduction Aryabhata Brahmagupta Bhaskara I Madhava ReferencesThanks Thanks ...V. N. Krishnachandran Vidya Academy of Science & Technology Thrissur 680 501, KeralaOn Finite Diﬀerences, Interpolation Methods and Power Series Expansions in Indian Mathematics

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