Hayanaratna · by Balabhadra
Chapter 1 · Planets, Signs, Year Entry
ग्रहराशिस्वरूपवर्षप्रवेशाद्यानयनाधिकारः
अथलग्नसाधनम् ॥यत्कालार्कस्सायनस्तस्य भोग्यैर्भागैर्निघ्नः स्वोदयः खाग्निभक्तः ॥भाग्यं जह्यादिष्टनाडीपलेभ्यः शेषादग्र्यान्स्वोदयांश्चावशेषम् ॥
Now finding the lagna (rising sign). Take the Sun at the wanted time and make it sayana (tropical). Multiply its sign's own rising time by the degrees it has still to go. Divide by 30. Subtract this from the wanted ghatikas (24-minute units) and palas (24-second units). From the rest, take away the rising times of the next signs too. Keep what is left.
Simple meaning: Finding the rising sign: take away the Sun's remaining time in its sign, then the rising times of the next signs.
त्रिंशन्निघ्नमशुद्धाप्तभागाद्यं मेषपूर्वकैः ॥
Rising sign degrees: remainder x 30, divided by the rising time of the next sign. Add to the signs passed, then remove the zodiac shift.
भोग्याल्पकालात्स्वत्रिघ्नात्स्वोदयाप्तलवादियुक् ॥
Rising sign when the wanted time is shorter than the Sun's remaining time: add a small part to the Sun itself. At night, start from the Sun plus six…
अत्र जन्मदेशीयमेषादिलग्नमानैर्लग्नस्पष्टीकरणं कर्तव्यं न त्वन्यदेशोदयैरिति ॥
Rising times: use those of the birth place, not another place.