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juliandate

Julian date calculator

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    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.

    example

    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.

    example

    Examples

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    Open Live Script

    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
    Open Live Script

    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
    Open Live Script

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

    jd = juliandate(2006,12,19)
    jd = 
2.4541e+06
    Open Live Script

    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

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

    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

    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

    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, 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, 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, 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, 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, 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, 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 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

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    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 Syntaxdy 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

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    See Also

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