enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Calendrical calculation - Wikipedia

    en.wikipedia.org/wiki/Calendrical_calculation

    The number of days between two dates, which is simply the difference in their Julian day numbers. The dates of moveable holidays, like Christian Easter (the calculation is known as Computus) followed up by Ascension Thursday and Pentecost or Advent Sundays, or the Jewish Passover, for a given year. Converting a date between different calendars.

  3. Determination of the day of the week - Wikipedia

    en.wikipedia.org/wiki/Determination_of_the_day...

    The Rata Die method works by adding up the number of days d that has passed since a date of known day of the week D. The day of-the-week is then given by (D + d) mod 7, conforming to whatever convention was used to encode D. For example, the date of 13 August 2009 is 733632 days from 1 January AD 1. Taking the number mod 7 yields 4, hence a ...

  4. Doomsday rule - Wikipedia

    en.wikipedia.org/wiki/Doomsday_rule

    Anytime adding 11 is needed, subtracting 17 yields equivalent results. While subtracting 17 may seem more difficult to mentally perform than adding 11, there are cases where subtracting 17 is easier, especially when the number is a two-digit number that ends in 7 (such as 17, 27, 37, ..., 77, 87, and 97).

  5. Day count convention - Wikipedia

    en.wikipedia.org/wiki/Day_count_convention

    This convention accounts for days in the period based on the portion in a leap year and the portion in a non-leap year. The days in the numerators are calculated on a Julian day difference basis. In this convention the first day of the period is included and the last day is excluded. The CouponFactor uses the same formula, replacing Date2 by Date3.

  6. Pascal's calculator - Wikipedia

    en.wikipedia.org/wiki/Pascal's_calculator

    He designed the machine to add and subtract two numbers directly and to perform multiplication and division through repeated addition or subtraction. Pascal's calculator was especially successful in the design of its carry mechanism, which adds 1 to 9 on one dial, and carries 1 to the next dial when the first dial changes from 9 to 0. His ...

  7. Gregorian calendar - Wikipedia

    en.wikipedia.org/wiki/Gregorian_calendar

    Up to 28 February in the calendar being converted from, add one day less or subtract one day more than the calculated value. Give February the appropriate number of days for the calendar being converted into. When subtracting days to calculate the Gregorian equivalent of 29 February (Julian), 29 February is discounted.

  8. Equation of time - Wikipedia

    en.wikipedia.org/wiki/Equation_of_time

    From 1767 to 1833, the British Nautical Almanac and Astronomical Ephemeris tabulated the equation of time in the sense 'add or subtract (as directed) the number of minutes and seconds stated to or from the apparent time to obtain the mean time'. Times in the Almanac were in apparent solar time, because time aboard ship was most often determined ...

  9. Sexagenary cycle - Wikipedia

    en.wikipedia.org/wiki/Sexagenary_cycle

    For both the stem and the branch, find the N for the row for the century, year, month, and day, then add them together. If the sum for the stems' N is above 10, subtract 10 until the result is between 1 and 10. If the sum for the branches' N is above 12, subtract 12 until the result is between 1 and 12.