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

211
(3) Taking the case of the Moon, the max correct-
ion amounts to (790 × 120) / 270 = 5' — 51''.
Verses 66, 67. The computation of Tithi, Nakṣatra
and Yoga.
The elongation of the Moon ie. the excess of the
Moon's longitude over that of the Sun in degrees. (In
case the former is smaller, add 360° to it and subtract
Sun's longitude) being divided by 12 and 6, the quotients
represent the elapsed tithis and Karaṇas. If the elapsed
Karanas are K, count K — 1 beginning from Bava to
get the current Karaṇa and count from Śakuni to get
the current one beginning from the mid-moment of
Kṛṣṇachaturdasī. Take again the planetary position or
that of the Moon in particular as well as the sum of
the longitudes of the Sun and the Moon both expressed
in minutes of arc and divided by 800. The first quotient
gives the elapsed stars ie. the Stars covered by the planet
or the Moon; whereas the second quotient gives the
elapsed Karaṇas. Then take the remainders in seconds
and divide by the respective daily motions in minutes i.e.
in the case of the planets or the Moon divide by their
respective motions and in the case of yogas divide by the
sum of the motions of the Sun and the Moon. Then the
results give the times in nādīs as to how much the next
nakṣatra or yoga have elapsed. If it be required to find
as to how long the next nakṣatra or yoga will last,
substract the remainder from 800, and divide by the daily
motions in minutes as mentioned above. The results
give as to how many nādīs beginning from the morning
concerned, the next nakṣatra or yoga will last.
Comm. (1) A lunation i.e. the time from the moment
of New Moon to the next New Moon is divided into
30 parts called Tithis. Their names are pratipat, Dwitiyā
etc. upto the 15th purnima or full Moon and again