Zeller’s congruence
E637292
Zeller’s congruence is a mathematical formula used to determine the day of the week for any given date in the Gregorian or Julian calendar.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Zeller’s congruence canonical | 1 |
Statements (44)
| Predicate | Object |
|---|---|
| instanceOf |
algorithm
ⓘ
calendar calculation method ⓘ mathematical formula ⓘ |
| appliesTo |
Gregorian calendar
NERFINISHED
ⓘ
Julian calendar NERFINISHED ⓘ |
| assumes | months January and February treated as months 13 and 14 of previous year in common formulation ⓘ |
| canBeImplementedIn | any programming language supporting integer arithmetic ⓘ |
| category |
congruence formulas
ⓘ
date and time algorithms ⓘ |
| computes | weekday from a congruence modulo 7 ⓘ |
| dependsOn | encoding of weekday numbers ⓘ |
| describedAs | closed-form expression for weekday calculation ⓘ |
| field |
calendar computation
ⓘ
discrete mathematics ⓘ number theory ⓘ |
| hasComponent |
floor functions in some formulations
ⓘ
term depending on century ⓘ term depending on shifted month ⓘ term depending on year of century ⓘ term proportional to day of month ⓘ |
| hasConstraint |
requires correct handling of century transitions
ⓘ
requires correct mapping between numeric result and weekday names ⓘ |
| hasVariant |
Zeller’s congruence for Gregorian calendar
NERFINISHED
ⓘ
Zeller’s congruence for Julian calendar NERFINISHED ⓘ |
| input |
century
ⓘ
day of month ⓘ month ⓘ year ⓘ |
| isAlternativeTo | table-based weekday methods ⓘ |
| namedAfter | Christian Zeller NERFINISHED ⓘ |
| output |
day of the week index
ⓘ
weekday name ⓘ |
| precision |
exact for valid Gregorian dates
ⓘ
exact for valid Julian dates ⓘ |
| relatedTo |
Doomsday rule
NERFINISHED
ⓘ
Gauss’s algorithm for the day of the week NERFINISHED ⓘ Tomohiko Sakamoto’s algorithm NERFINISHED ⓘ |
| requires | distinguishing between Gregorian and Julian calendar systems ⓘ |
| typicalDomain |
calendar software
ⓘ
computer date libraries ⓘ historical date analysis ⓘ |
| usedFor | determining the day of the week ⓘ |
| usesOperation |
integer division
ⓘ
modular arithmetic ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.