Instructions: Enter the four digit year. Press [ R/S ]. The month will be displayed (stored in R1). Press [ R/S ] to get the day (stored in R2).
For background information and notes, click here:
http://edspi31415.blogspot.com/2016/09/h...aster.html
HP12C Platinum Program: Easter
Code:
STEP CODE KEY Notes
001 44, 0 STO 0 Store year (y)
002 1 1
003 25 %
004 43, 25 INTG
005 44, 1 STO 1 Store c
006 44, 4 STO 4 Start i
007 36 ENTER To fill the stack
008 36 ENTER
009 4 4
010 10 ÷
011 43, 25 INTG
012 44, 30, 4 STO- 4
013 33 R↓
014 36 ENTER
015 36 ENTER
016 1 1
017 7 7
018 30 -
019 2 2
020 5 5
021 10 ÷
022 43, 25 INTG
023 44, 3 STO 3 Store k
024 30 -
025 3 3
026 10 ÷
027 43, 25 INTG
028 44, 30, 4 STO- 4
029 1 1
030 5 5
031 44, 40, 4 STO+ 4
032 45, 0 RCL 0
033 1 1
034 9 9
035 10 ÷
036 43, 40 LSTx LSTx is [ g ] [ + ] on the Platinum
037 34 X<>Y
038 43, 24 FRAC
039 20 * y MOD 19
040 44, 2 STO 2 Store n
041 1 1
042 9 9
043 20 *
044 44, 40, 4 STO+ 4
045 45, 4 RCL 4
046 3 3
047 0 0
048 10 ÷
049 43, 40 LSTx
050 34 X<>Y
051 43, 24 FRAC
052 20 *
053 44, 4 STO 4 i MOD 30
054 2 2
055 7 7
056 45, 4 RCL 4
057 43, 44 x≤y Is i≤27?
058 43, 33, 080 GTO 080 If so, go to step 080
059 2 2
060 9 9
061 45, 4 RCL 4
062 1 1
063 40 +
064 10 ÷
065 43, 25 INTG
066 20 *
067 1 1
068 34 X<>Y
069 30 -
070 2 2
071 1 1
072 45, 2 RCL 2
073 30 -
074 1 1
075 1 1
076 10 ÷
077 43, 25 INTG
078 20 *
079 44, 30, 4 STO- 4
080 45, 0 RCL 0
081 45, 2 STO 2 Start j
082 4 4
083 10 ÷
084 43, 25 INTG
085 44, 40, 2 STO+ 2
086 45, 4 RCL 4
087 2 2
088 40 +
089 45, 1 RCL 1
090 30 -
091 44, 40, 2 STO+ 2
092 45, 1 RCL 1
093 4 4
094 10 ÷
095 43, 25 INTG
096 44, 40, 2 STO+ 2
097 45, 2 RCL 2
098 7 7
099 10 ÷
100 43, 40 LSTx
101 34 X<>Y
102 43, 24 FRAC
103 20 *
104 44, 2 STO 2 j MOD 7
105 45, 4 RCL 4
106 34 X<>Y
107 30 -
108 44, 3 STO 3 Store l
109 4 4
110 0 0
111 40 +
112 4 4
113 4 4
114 10 ÷
115 43, 25 INTG
116 3 3
117 40 +
118 44, 1 STO 1 Store month (m)
119 31 R/S Displays m
120 4 4
121 10 ÷
122 43, 25 INTG
123 3 3
124 1 1
125 20 *
126 16 CHS
127 2 2
128 8 8
129 40 +
130 45, 3 RCL 3
131 40 +
132 44 , 2 STO 2 Store day (d)
133 43, 33, 000 GTO 000 Stop, display d
Examples and Test Data:
2016: 3, 27
Keystrokes: 2016 [R/S] [R/S]
1995: 4, 16
2124: 4, 2
1977: 4, 10
2017: 4, 16
1826: 3, 26
These results have been verified.
Source: The United States Naval Observatory “The Date of Easter” March 11, 2016.
http://aa.usno.navy.mil/faq/docs/easter.php Retrieved September 2, 2016