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

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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