Āryabhaṭīya with the Commentary (with commentary) · Chapter 21

chāyāguṇitam chāyayā guṇitam | kim chāyāguṇitam ? chāyāgravivaram, chāyāgrayoḥ vivaram chāyāgravivaram, chāyāgrāntarālabhūmiḥ iti arthaḥ | tat yathā ã anirjñātocchrāyayaṣṭipradīpāt kiyat api apasṛtya śaṅkuḥ sthāpitaḥ | tasya chāyā jñāyate eva | tacchāyāgrāt parigaṇite antare dvitīyaśaṅkuḥ, tacchāyāgrāt pūrvaśaṅkucchāyāgram iti antaram chāyāgravivaram | tadiṣṭayā prathamacchāyayā dvitīyacchāyayā vā guṇitam | ūnena bhājitam, ūnam chāyayoḥ
viśeṣaḥ, tena ūnena bhājitam | koṭī avasānabhūmiḥ | tat yadi prathamacchāyayā guṇitam tadā prathamacchāyāgrayaṣṭipradīpāntarālam bhavati, dvitīyayā chāyayā yadi tadagrayaṣṭipradīpāntarālam | śaṅkuguṇā koṭī, śaṅkuḥ guṇaḥ yasyāḥ sā iyam śaṅkuguṇā koṭī | chāyābhaktā bhujā bhavati, bhujā yaṣṭipradīpocchrāyaḥ | chāyādvayam api tatkoṭibhyām prasādhyate |
uddeśakaḥ ã
śaṅkoḥ samayoḥ dṛṣṭe kramaśaḥ daśaṣoḍaśāṅgule chāye |
agrāntaram ca dṛṣṭam triṃśat koṭībhuje vācye

nyāsaḥ ã
parilekhaḥ 41
karaṇam ã chāyāgravivaram 30, etat prathamacchāyāguṇitam 300; chāyayoḥ viśeṣaḥ 6, anena labdham koṭī 50; iyam eva koṭī śaṅkuguṇā jātā 600, chāyābhaktā bhujā 60 | dvitīyacchāyātaḥ api koṭī 80, bhujā sā eva 60 |
uddeśakaḥ ã
pañca sapta kramāt chāye narayoḥ tulyayoḥ smṛte |
aṣṭau agrāntaram dṛṣṭam bhujakoṭī tadā ucyatām

nyāsaḥ ã
parilekhaḥ 42
pūrvavat labdhā koṭī 20, bhujā 48 | dvitīyacchāyātaḥ api koṭī 28, bhujā sā eva 48 |
viṣuvat ahani gaganatala[madhya]vartini savitari samadakṣiṇottaradeśacchāyāgrāntarālayojanaiḥ chāyāviśeṣeṇa śaṅkunā [ca] kecit vivasvadavanitalāntarālayojanāni ānayanti, tat ayuktam | atra pradīpacchāyādvayakarmālāpāvatāraḥ api na upapadyate | kutaḥ ? yasmāt āha "bhūravivivaram vibhajet" [golaí, 39 ] iti | bhūḥ śaṅkuḥ, raviyojanakarṇaḥ śaṅkubhujāvivaram, sakalajagadekapradīpaḥ bhagavān bhāskaraḥ svayam eva pradīpocchrāyaḥ iti ataḥ
vivasvadavanitalāntarālayojanānayanam na ghaṭate, "bhūravivivaram" iti siddhānām eva yojanānām upadeśāt | atha savitā eva pradīpocchrāyaḥ iti savitṛviṣkambhapramāṇam ānīyate iti cet, tat ca na | yasmāt svakakṣyākarṇabhūvivarayojanaḥ gaganatalamadhyāsīnaḥ lokān dyotayan lakṣyate, tasmāt pradīpocchrāyaḥ svayam savitā [na] bhavitum arhati | atha vivasvān pradīpocchrāyaḥ, savitṛdharitrīmadhyāntarālayojanāni aśeṣāvanitalamaṇḍalavyāsapramāṇasya śaṅkoḥ
vivaram, tathā ca dvitīyasya tāvat śaṅkoḥ avasthānābhāvāt ca na yujyate | tasmāt suṣṭhu uktam "pradīpacchāyā[dvaya]karmālāpāvatāraḥ api na upapadyate " iti |
iyam ca dharitrī golākārā paṭhyate | tena tatpṛṣṭhavartinām asmākam vakratvāt paridheḥ śaṅkucchāyā bhujakoṭikarmaparikalpanā atra [na] pravartate, yataḥ salilasamīkṛte pradeśe śaṅkucchāyayā bhujākoṭikarṇakṣetrasaṃsthānam, na ca etāvatyā bhuvaḥ śakyate samīkaraṇam kartum | atha abhyupagamya idam udāhriyate ã viṣuvatī ujjayinyām dinārdhavartinī uṣṇadīdhitau chāyā pañcāṅgulā | tayā akṣaḥ labdhaḥ bhāgāḥ dvāviṃśatiḥ liptāḥ saptatriṃśat
| anena akṣeṇa laṅkojjayinyantarālayojanāni labdhāni saptāmbarayamasaṅkhyāni 207 | tataḥ ujjayinyā uttareṇa viṣuvatī eva madhyāhnacchāyā sthāneśvare saptāṅgulā | tayā ca akṣaḥ labhdaḥ bhāgāḥ triṃśat sapādāḥ | anena akṣeṇa laṅkāsthāneśvarāntarālayojanāni labdhāni śarādriyamasaṅkhyāni 275 | atra eteṣām yojanānām viśeṣaḥ aṣṭaṣaṣṭiḥ śaṅkudvayavivaram, chāyayoḥ antareṇa dvābhyām yuktā aṣṭaṣaṣṭiḥ, chāyāgravivaram saptatiḥ | atra gaṇitakarma "chāyāguṇitam
chāyāgravivaram" iti ādikarmaṇā koṭiyojanāni labhyante | taiḥ ca dvitīyacchāyayā nīyamānaiḥ laṅkāsthāneśvarāntarālayojanaiḥ eva bhavitavyam , yasmāt tasmin kāle vivasvadadhovasthitaḥ deśaḥ laṅkā | yadi vivasvān bhujā yadi vā vivasvataḥ yaḥ ucchrāyaḥ, tasmāt koṭeḥ laṅkāsthāneśavarāntarālayojanasaṅkhyānatvāt gaṇitakarma api atra na krāmati | atra ca yayā koṭyā bhujā sādhyate sā ca tāvat na siddhā, tayā asiddhayā siddhabhujā sādhyate iti etat ayuktam | anyat
ca yat chāyā dvādaśāṅgulasya śaṅkoḥ pratyakṣam asmābhiḥ upalabdhā tayā āṅgulapramāṇayā yojanaiḥ karma kriyate iti etat ca na upapadyate | atha dvādaśayojanapramāṇasya śaṅkoḥ pañcayojanā saptayojanā ca chāyā iti etat api tāvataḥ śaṅkoḥ lambakena ṛjusthitiḥ aśakyā jñātum, na ca utkṣepaṇasthāpane | chāyā ca samāyāmavanau sādhyate tāvatsu yojaneṣu nimnonnatasarit iti ādiviṣamatā tena tadavagatiḥ na śakyate | tasmāt yathā āgamasiddhau eva sahasramarīceḥ
ucchrāyaviṣkambhau | tataḥ na atra iyam gaṇitaprakriyāprakāravāgurā prasāraṇīyā iti