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

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the case of the Inferior planets, the Sighraphala will be
itself their elongation eastern or western. Then they
rise in the West, being near Superior conjunction. When
again their Sighra anomalies equal respectively 155° and
177°, the same Sighraphalas will arise so that they set
heliacally in the West. Then as the Sighra anomalies
attain the symmetrical values on the other side ie. (360-
155) and (360-177) ie. 205° and 183° the Sighraphalas being
the same, they rise in the East. Again when they attain
the values (360-50) and (360-24) ie. 310° and 336°, they
set in the East on account of the same Sighraphalas or
Kālāmsas.
Verse 44. When the Sighra anomalies have parti-
cular values, to decide when the planets rise or set helia-
cally, we have to take the difference of those particular
values and the numbers given above for the respective
Sighra anomalies, convert them into minutes of arc and
divide the results by the daily motion in the Sighra ano-
malies in minutes of arc. Then we have the number of
days in which the rising or setting takes place thereafter.
Comm. Suppose it is required when Mercury rises in
the West. Suppose we want to compute this on a parti-
cular day when Mercury's Sighra anomaly is x°. Then
because we know that Mercury rises in the West when his
Sighra anomaly is 50, we have to calculate by how many
days the difference | x-50 | of the Sighra anomaly would
be covered. Let the daily motion of the Sighra anomaly
be y' per day, Then by rule of three (| x-50 | × 60) / y will
be the number of days before or after as the case may be
for Mercury to rise in the West.
Verse 45. To obtain the Mean planet knowing the
True.
Assume the True planet to be the Mean; compute the
Manda and Sighraphalas and applying them inversely,