Surya Siddhanta
दिग्भेदे +अपक्रमः शेषस् तस्य ज्या त्रिज्यया हता । परमापक्रमज्याप्ता चापम् मेषादिगो रविः॥
Divide the product by the sine of the Sun's greatest declination (or 1397): find the arc (in signs &c. whose sine is equal to the quotient, just found); this arc will be the longitude of the Sun when he is in the first quarter of the Ecliptic: but when he is in the second or third quarter, subtract or add the signs &c. (contained in the arc) from or to 6 signs; (the remainder or the sum will be the longitude of the Sun).
english translation
digbhede +apakramaH zeSas tasya jyA trijyayA hatA । paramApakramajyAptA cApam meSAdigo raviH॥
hk transliteration by Sanscript