MATLAB: Convert Modified Julian Date

conversiondate

I am importing a .dat file that has MJD in the form of "55743.21235" and if converted in Excel (by taking the cell-50813) is 06/30/11 05:05:47. This is cummlative file with years worth of data but each quarter, I am only interested in the current quarter(i.e. Oct 01, 2011-Dec 31, 2011).
How can I convert/change each of the MJDs (in a single column of over +1000 MJDs) that I import into the more meaningful form of 'dd:mmm:yyyy' or 'mmm:dd:yyyy'? Once the conversion is complete, the user will be queried to select a time frame, or quarter, of interest. The HH:MM:SS aren't required. Thanks, Kate

Best Answer

The difference between datenum('06/30/11 05:05:47') (your proposed translation) and 55743.21235, is 678941
However, datenum('Nov 17, 1858,00:00') is 678942, which is a one day difference compared to your proposal.
The Nov 17, 1858 00:00 date is listed in Wikipedia, and the 678942 offset is exactly that needed to properly convert the example MJD 49987 to September 27, 1995, as documented in the US Naval Observatory web site
The evidence would seem to suggest that your calculations are off by exactly one day, and that Fangjun's calculations are correct.
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