सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

224 give the rising time of the arc of (30 — r)° of that Rāśi are called the Bhogyāsus, or the asus which are taken by the remainder of the Rāśi to rise at the place. They are equal to. ((30 — r) × T) / 30 where T gives the asus of the rising time of that Rāśi. The Bhuktāsus on the other hand are the asus which pertain to the rising time of the arc of the first r° of that Rāśis, which are therefore equal to (r × 𝒯) / 30 ; from the given time substract the Bhogyāsus formulated above; then substract also the rising times of as many subsequent Rāśis as could be substracted. Let 'R' be the remainder of the time given. If t be the rising time in asus of the next Rāśi, (R × 30°) / t gives the number of degrees by which the lagna has advanced in the next Rāśi. These degrees added to the previous Rāśis beginning from ♈ the equinoctial point give the Sāyana or the modern longitude of the lagna. From this Sāyana longitude if we substract the Ayanamsa, we have the Nirayana or the Hindu longitude measured from the Hindu Zero-point of the ecliptic. If, however, the given time after Sun-rise expressed in asus say 'a' falls short of the Bhogyāsus defined above, then, (a × 30) / 𝒯 where 𝒯 is the rising time in asus of the Rāśi in which the Sun is situated, added to the longitude of the Sun, gives the Sāyana longitude of the lagna. Comm. The substance of these verses, though appears to be simple, yet is complicated which can be better under- stood with the help of a figure (Ref. fig. 30). Let SEN be the horizon, ♈ER the celestial equator and ♈AL the ecliptic where L is the point of lagna. Required to find ♈L the Sāyana longitude of L from which if Ayanamsa be substracted we get the Hindu