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juliandate

Julian date calculator

    Description

    example

    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 dy = juliandate([year,month,day]) return the Julian date for corresponding elements of the year,month,day arrays.

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

    Examples

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    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 for December 19, 2006 from year, month, and day inputs:

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

    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+006

    Input Arguments

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    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 one-dimensional 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.

    If the format does not contain enough information to compute a date number, then:

    • Hours, minutes, and seconds default to 0.

    • Days default to 1.

    • Months default to January.

    • Years default to the current year.

    Data Types: char | string

    Year, specified as a scalar or one-dimensional array.

    Dates with two character years are interpreted to be within 100 years of the current year.

    Dependencies

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

    Data Types: char | string

    Month, specified as a scalar or one-dimensional array from 1 to 12.

    Dependencies

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

    Data Types: double

    Day, specified as a scalar or one-dimensional array from 1 to 31.

    Dependencies

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

    Data Types: double

    Hour, specified as a scalar from 0 to 24.

    Dependencies

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

    Data Types: double

    Minute, specified as a double, whole number from 0 to 60.

    Dependencies

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

    Data Types: double

    Second, specified as a double, whole number from 0 to 60.

    Dependencies

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

    Data Types: double

    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

    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.

    Introduced in R2006b