Page:Sewell Dikshit The Indian Calendar (1896) proc.djvu/90

to South Malayâḷam Âṇḍu 1024, 20th Chiṅgam, and to the same day of the month in the North Malayâḷam (Kollam) Âṇḍu 1023, the reason being that in the former reckoning the year begins with Chiṅgam, and in the latter with Kanni.]

Example 11. Required the A.D. equivalent of the Tamil date, 20th Paṅguni of Rudhirodgârin, K.Y. 4905 current (or 4904 expired.)

Table I. gives (${\displaystyle d}$) 11th April (101), 1803 A.D. as the initial date of the solar year, and its week-day (${\displaystyle w}$) is (2) Monday.

Answer.—Friday, March 30th, 1804. (See example i, above.)

138. (B.) Conversion of dates A.D. into Hindu dates. (See Art. 135 above, par. 1.)

Rule I. Given a year, month, and date A.D. Write down in a horizontal line (${\displaystyle d}$) the date-indicator of the initial date [in brackets (Table I., cols. 13 or 19, as the case may be)] of the corresponding Hindu year required, and (${\displaystyle w}$) the week-day number of that initial date (col. 14 or 20), remembering that, if the given date A.D. is earlier than such initial date, the (${\displaystyle d}$) and (${\displaystyle w}$) of the previous Hindu year must be taken. Subtract the date-indicator from the date number of the given A.D. date in Table IX., remembering that, if the previous Hindu year has been taken down, the number to be taken from Table IX. is that on the right-hand side of the Table and not that on the left. From the result subtract (Table III., col. 3a or 10) the collective-duration-figure which is nearest to, but lower than, that amount, and add 1 to the total so obtained; and to the (${\displaystyle w}$) add the figure resulting from the second process under (${\displaystyle d}$), and divide by 7. The result gives the required week-day. The resulting (${\displaystyle d}$) gives the day of the Hindu month following that whose collective duration was subtracted.

Rule II. Observe (Table I., cols. 8 or 8a) if there has been an addition or suppression of a month prior to the month found by Rule I. and proceed accordingly.

An easy rule for dealing with the added and suppressed month is the following. When the intercalated month (Table I., col. 8 or 8a) precedes the month immediately preceding the one found, such immediately preceding month is the required month; when the intercalated month immediately precedes the one found, such immediately preceding month with the prefix "nija," natural, is the required month; when the intercalated month is the same as that found, such month with the prefix "adhika" is the recjuircd month. When a suppressed month precedes the month found, the required month is the same as that found, because there is never a suppression of a month without the intercalation of a previous month, which nullifies the suppression so far as regards the collective duration of preceding days. But if the given month falls after two intercalations and one suppression, act as above for one intercalation only.

Rule III. See Art. 137 (A) Rule V. (p. 70), but subtract the eleven days instead of adding.

Rule IV. If the given A.D. date falls in a leap-year after 29th February, or if its date-number