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

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we have f' − (A × G) / M = I' + F where I' is some integer other
than I. But (A × D) / M which gives us the number of
diurnal rotations of the stars upto the day concerned is
equal to the Ahargaṇa plus the number of revolutions of
the Sun upto the day concerned, because Ahargaṇa +
Revolutions of the Sun = diurnal rotations of the stars
upto the day concerned. Omitting the integral Ahargaṇa
and the integral number of revolutions of the Sun we have
that the fractional part of (A × D) / M ie f' is no other than
the Sun's position. Hence.
(A × P) / M = I + F = f' − (A × G) / M and (A × G) / M =
(A × G) / 1577916450000 revolutions = (12 R) / 1577916450000 Rasis =
R / 131493037500 Rasis. Thus the planetary position is
equal to the Sun's position minus (A × G) / 131493037500 where the
integral parts on either side could be ignored.
Here there is a peculiarity in this method. The planet
could right away be obtained from the formula (A × P) / M
where A is the Ahargaṇa, P the number of sidereal revolu-
tions of the planet and M the number of mean Solar days
in a Kalpa. Though the given method is more cumbrous
than finding through the above formula, Bhaskara delibe-
rately gives it to show the equivalence of various proce-
dures at the same time giving us a beautiful technique as
mentioned in his commentary. Thus in the above equation
(A × P) / M = (A × D) / M − (A × G) / M the first term on the right
hand side could be termed the Bha-bhrama-graha and the
second term (A × G) / M the graha-Sāvana-Dina-graha. We