juliandate

Julian date calculator

Syntax

jd = juliandate(datetime)

jd = juliandate(dateVector)

jd = juliandate(dateCharacterVector,format)

jd = juliandate(year,month,day)

jd = juliandate([year,month,day],'Action'=value)

jd = juliandate(year,month,day,hour,minute,second,'Action'=value)

jd = juliandate([year,month,day,hour,minute,second],'Action'=value)

Description

jd = juliandate(datetime) converts one or more datetime arrays to Julian date, jd.

jd = juliandate(dateVector) converts one or more date vectors, dateVector, to Julian date, jd.

jd = juliandate(dateCharacterVector,format) converts one or more date character vectors, dateCharacterVector, to Julian date, jd, using format format.

jd = juliandate(year,month,day) and jd = juliandate([year,month,day],'Action'=value) return the Julian date for corresponding elements of the year,month,day arrays.

jd = juliandate(year,month,day,hour,minute,second,'Action'=value) and jd = juliandate([year,month,day,hour,minute,second],'Action'=value) return the Julian date for corresponding elements of the year,month,day,hour,minute,second arrays. Specify the six arguments as 1-D arrays of the same length or scalar values.

Examples

Calculate Julian Date Using datetime Array

Calculate the Julian date for February 4, 2016, from datetime array.

dt = datetime('04-02-2016','InputFormat','dd-MM-yyyy')

dt = datetime
   04-Feb-2016

jd = juliandate(dt)

jd = 
2.4574e+06

Calculate Julian Date Using Date Character Version and dd-mm-yyyy Format

Calculate Julian date for May 24, 2005, using date character version and dd-mm-yyyy format.

jd = juliandate('24-May-2005','dd-mmm-yyyy')

jd = 
2.4535e+06

Calculate Julian Date Using Year, Month, and Day Inputs

Calculate Julian date for December 19, 2006, from year, month, and day inputs.

jd = juliandate(2006,12,19)

jd = 
2.4541e+06

Calculate Julian Date from Year, Month, Day, Hour, Minute, and Second Inputs

Calculate Julian date for October 10, 2004, at 12:21:00 p.m. from year, month, day, hour, month, and second inputs.

jd = juliandate(2004,10,10,12,21,0)

jd = 
2.4533e+06

Input Arguments

datetime — datetime array

m-by-1 array | 1-by-m array

datetime array, specified as an m-by-1 array or 1-by-m array.

dateVector — Full or partial date vector

m-by-6 matrix | m-by-3 matrix | positive double-precision number

Full or partial date vector, specified as an m-by-6 or m-by-3 matrix containing m full or partial date vectors, respectively:

• Full date vector — Contains six elements specifying the year, month, day, hour, minute, and second

• Partial date vector — Contains three elements specifying the year, month, and day

Data Types: double

dateCharacterVector — Date character vector

character array | 1-D cell array of character vectors

Date character vector, specified as a character array, where each row corresponds to one date, or a 1-D cell array of character vectors.

Data Types: char | string

format — Date format

-1 (default) | character vector | string scalar | integer

Date format, specified as a character vector, string scalar, or integer. All dates in dateCharacterVector must have the same format and use the same date format symbols as the datenum function.

juliandate does not accept formats containing the letter Q.

Data Types: char | string

year — Year

positive scalar | 1-D array | decimal

Year, specified as a positive scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: char | string

month — Month

positive or negative scalar | 1-D array | decimal

Month, specified as a positive or negative scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: double

day — Day

positive or negative scalar | 1-D array | decimal

Day, specified as a positive or negative scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: double

hour — Date format

positive or negative scalar | 1-D array | decimal

Hour, specified as a positive or negative scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: double

minute — Minute

positive or negative scalar | 1-D array | decimal

Minute, specified as a positive or negative scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: double

second — Second

positive or negative scalar | 1-D array | decimal

Second, specified as a positive or negative scalar or 1-D array.

Dependencies

Depending on the syntax, specify year, month, and day or year, month, day, hour, minute, and second as 1-D arrays of the same length or scalar values.

Data Types: double

'Action'=value — Action

'Warning' (default) | 'Error' | 'None'

Action for noninteger decimal date input for year, month, day, hour, and minute, specified as:

• 'Error' — Displays error and total number of noninteger date values.

• 'Warning' — Displays warning and total number of adjusted noninteger date values. The function adjusts the noninteger value to its integer equivalent before calculating the value.

• 'None' — Does not display warning or error. The function adjusts the noninteger value to its integer equivalent before calculating the value.

Data Types: char | string

Output Arguments

jd — Julian date

m-by-6 column vector | m-by-3 column vector | row vector | column vector

Julian date, returned as a column vector of m Julian dates, which are the number of days and fractions since noon Universal Time on January 1, 4713 BCE.

• m-by-6 column vector — Contains six elements specifying the year, month, day, hour, minute, and second

• m-by-3 column vector — Contains three elements specifying the year, month, and day

• Row or column vector — Contains m Julian dates

Dependencies

The output format depends on the input format:

Input Syntax	dy Format
jd = juliandate(dateVector)	m-by-6 column vector or m-by-3 column vector of m Julian dates.
jd = juliandate(dateCharacterVector,format)	Column vector of m Julian dates, where m is the number of character vectors in dateCharacterVector.

Limitations

The calculation of Julian date does not take into account leap seconds.

Version History

Introduced in R2006b

R2022b: juliandate accepts decimal values

The juliandate function now accepts decimal values for these input arguments:

• year

• month

• day

• hour

• minute