Julian Day Shortcut Formulas
Here are a couple of formulas that can be used to quickly get the Julian Day. (I haven't figured how to include the time yet).
HP Prime (Rev. 7820):
yyyy: four digit year, mm: two digit month, dd: two digit day. The international date format is used.
From December 31, 1899:
JD = DDAYS(1899.1231,yyyy.mmdd) + 2415020
Alternatively, from November 16, 1858:
JD = DDAYS(1858.1116, yyyy.mmdd) + 2.4E6
TI-84 (and BA II Plus to that extent):
Dates are good from January 1, 1950 to December 31, 2049:
JD = dbd(1.0150, mm.ddyy) + 2433283
The days between dates function (dbd) is accessed by pressing [ APPS ], [ 1 ], [ALPHA], [ x^-1] (D).
Casio Prizm and fx-Graphing calculators:
Dates are good from January 1, 1901 to December 31, 2099:
JD = Days_Prd(1,1,1901,mm,dd,yyyy) + 2415386
Where to find Days_Prd: [ OPTN ], ( > ) (until you see the FINANCE sub menu), (FINANCE), ( > ), (DAYS), (PRD)
Hope you find this helpful.
Source:
"Julian Day" http://en.wikipedia.org/wiki/Julian_day Retrieved May 28, 2015
Eddie
This blog is property of Edward Shore. 2015.
Here are a couple of formulas that can be used to quickly get the Julian Day. (I haven't figured how to include the time yet).
HP Prime (Rev. 7820):
yyyy: four digit year, mm: two digit month, dd: two digit day. The international date format is used.
From December 31, 1899:
JD = DDAYS(1899.1231,yyyy.mmdd) + 2415020
Alternatively, from November 16, 1858:
JD = DDAYS(1858.1116, yyyy.mmdd) + 2.4E6
TI-84 (and BA II Plus to that extent):
Dates are good from January 1, 1950 to December 31, 2049:
JD = dbd(1.0150, mm.ddyy) + 2433283
The days between dates function (dbd) is accessed by pressing [ APPS ], [ 1 ], [ALPHA], [ x^-1] (D).
Casio Prizm and fx-Graphing calculators:
Dates are good from January 1, 1901 to December 31, 2099:
JD = Days_Prd(1,1,1901,mm,dd,yyyy) + 2415386
Where to find Days_Prd: [ OPTN ], ( > ) (until you see the FINANCE sub menu), (FINANCE), ( > ), (DAYS), (PRD)
Hope you find this helpful.
Source:
"Julian Day" http://en.wikipedia.org/wiki/Julian_day Retrieved May 28, 2015
Eddie
This blog is property of Edward Shore. 2015.