Name

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      YDN2MD

Purpose

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      Convert from year and day number of year to month and day of month.

Calling Sequence

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      YDN2MD,yr,dy,m,d

Inputs

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      yr = 4 digit year (like 1988), integer scalar
      dy = day number in year (like 310), integer scalar or vector

Outputs

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      m = month number (1-12, e.g. 11 = Nov)
      d = day of month (like 5).
      Note: On error returns m = d = -1.

Example

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      Find the month/day of days 155 and 255 in the year 2001
      IDL> ydn2md, 2001, [155,255], m, d
        ==> m = [6,9] & d = [4,12] ; = June 4 and September 12
     

Modification History

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      Adapted from Johns Hopkins University/Applied Physics Laboratory
      Update to use VALUE_LOCATE, W. Landsman January 2001