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

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4, 5 we have seen how BC is computed. Here we are
seeking to compute AC through the corresponding arc ap
of the diurnal circle.
The verse uses the word Sphuta-Krānti, Asphuta-
Krānti, and their Cara-khandas. Here in the figure pC
is the Sphuta-Krānti and p'B is the Asphuta-Krānti or
simply Krānti. Also pp' is called Asphuta-Vikṣēpa and
bp' Sphuta-Vikṣēpa. Sphuta-Krānti = pc = bB = bp' + p'B =
Sphuta-Vikṣēpa + Asphuta-Krānti. In other words the
declination of p, the planet, is called Sphuta-Krānti and
that of its longitudinal position on the ecliptic namely p'
is called Asphuta-Krānti or simply Krānti. We have
obtained Sphuta-Krānti from Krānti by adding to the
latter the Sphuta-Vikṣēpa. The method of obtaining
Sphuta-Vikṣēpa from the Vikṣēpa, otherwise called Vikṣēpa
Sphuta-karama was dealt with in verse 3 above.
Now we have to define the Cara-khandas pertaining
to the Sphuta-Krānti pC and the Asphuta-Krānti p'B.
The former is defined as AE and the latter by CE very
approximately. We say very approximately because when
p' comes to the horizon, the Cara-khanda will not be
exactly EC but a little more or less than EC since
Bp' ≠ Cq. In other words, the arc of the equator between
the declination circle of q while rising and the equatorial
horizon ie. AE is defined as the Cara-khanda of pC ;
similarly CE is that of p'B. Their difference is
AE—CE = AC. If we use the modern notation, we have
to take their algebraical difference. If that be done, the
alternative case of adding the Cara-khandas when the
Sphuta and the Asphuta-Krānti are of opposite directions,
will be automatically implied. The asus pertaining to
this arc AC will be the correction of Ākṣa-Dṛk-karma as
mentioned in verse (6) when the latitude of the planet is
appreciable. These asus will be equal to the time taken by
p the planet to cover the arc ap or what is the same, the