How do I get correct dates for seasonal sst data (JJAS) using datenum function?

Respected All, I am a beginner to Matlab. I have 4months sst data per every year from 1980 to 2010. How do I get correct dates for that using datenum function? I am getting dates are as follows. Could you please help me in this context? Please check the below script. 01-Jun-1980 00:00:00 29-Aug-1980 09:36:00 26-Nov-1980 19:12:00 24-Feb-1981 04:48:00 24-May-1981 14:24:00 22-Aug-1981 00:00:00 19-Nov-1981 09:36:00 16-Feb-1982 19:12:00 17-May-1982 04:48:00 14-Aug-1982 14:24:00 12-Nov-1982 00:00:00 09-Feb-1983 09:36:00 09-May-1983 19:12:00 07-Aug-1983 04:48:00 04-Nov-1983 14:24:00 02-Feb-1984 00:00:00 01-May-1984 09:36:00 29-Jul-1984 19:12:00 27-Oct-1984 04:48:00 24-Jan-1985 14:24:00 24-Apr-1985 00:00:00 22-Jul-1985 09:36:00 19-Oct-1985 19:12:00 17-Jan-1986 04:48:00 16-Apr-1986 14:24:00 15-Jul-1986 00:00:00 12-Oct-1986 09:36:00 09-Jan-1987 19:12:00 09-Apr-1987 04:48:00 07-Jul-1987 14:24:00 05-Oct-1987 00:00:00 02-Jan-1988 09:36:00 31-Mar-1988 19:12:00 29-Jun-1988 04:48:00 26-Sep-1988 14:24:00 25-Dec-1988 00:00:00 24-Mar-1989 09:36:00 21-Jun-1989 19:12:00 19-Sep-1989 04:48:00 17-Dec-1989 14:24:00 17-Mar-1990 00:00:00 14-Jun-1990 09:36:00 11-Sep-1990 19:12:00 10-Dec-1990 04:48:00 09-Mar-1991 14:24:00 07-Jun-1991 00:00:00 04-Sep-1991 09:36:00 02-Dec-1991 19:12:00 01-Mar-1992 04:48:00 29-May-1992 14:24:00 27-Aug-1992 00:00:00 24-Nov-1992 09:36:00 21-Feb-1993 19:12:00 22-May-1993 04:48:00 19-Aug-1993 14:24:00 17-Nov-1993 00:00:00 14-Feb-1994 09:36:00 14-May-1994 19:12:00 12-Aug-1994 04:48:00 09-Nov-1994 14:24:00 07-Feb-1995 00:00:00 07-May-1995 09:36:00 04-Aug-1995 19:12:00 02-Nov-1995 04:48:00 30-Jan-1996 14:24:00 29-Apr-1996 00:00:00 27-Jul-1996 09:36:00 24-Oct-1996 19:12:00 22-Jan-1997 04:48:00 21-Apr-1997 14:24:00 20-Jul-1997 00:00:00 17-Oct-1997 09:36:00 14-Jan-1998 19:12:00 14-Apr-1998 04:48:00 12-Jul-1998 14:24:00 10-Oct-1998 00:00:00 07-Jan-1999 09:36:00 06-Apr-1999 19:12:00 05-Jul-1999 04:48:00 02-Oct-1999 14:24:00 31-Dec-1999 00:00:00 29-Mar-2000 09:36:00 26-Jun-2000 19:12:00 24-Sep-2000 04:48:00 22-Dec-2000 14:24:00 22-Mar-2001 00:00:00 19-Jun-2001 09:36:00 16-Sep-2001 19:12:00 15-Dec-2001 04:48:00 14-Mar-2002 14:24:00 12-Jun-2002 00:00:00 09-Sep-2002 09:36:00 07-Dec-2002 19:12:00 07-Mar-2003 04:48:00 04-Jun-2003 14:24:00 02-Sep-2003 00:00:00 30-Nov-2003 09:36:00 27-Feb-2004 19:12:00 27-May-2004 04:48:00 24-Aug-2004 14:24:00 22-Nov-2004 00:00:00 19-Feb-2005 09:36:00 19-May-2005 19:12:00 17-Aug-2005 04:48:00 14-Nov-2005 14:24:00 12-Feb-2006 00:00:00 12-May-2006 09:36:00 09-Aug-2006 19:12:00 07-Nov-2006 04:48:00 04-Feb-2007 14:24:00 05-May-2007 00:00:00 02-Aug-2007 09:36:00 30-Oct-2007 19:12:00 28-Jan-2008 04:48:00 26-Apr-2008 14:24:00 25-Jul-2008 00:00:00 22-Oct-2008 09:36:00 19-Jan-2009 19:12:00 19-Apr-2009 04:48:00 17-Jul-2009 14:24:00 15-Oct-2009 00:00:00 12-Jan-2010 09:36:00 11-Apr-2010 19:12:00 10-Jul-2010 04:48:00

 Thanks in advance for any help,

best regards, Nagarjuna. email:[e-mail]

Answer 1

[Peter Perkins]

Unless you are using a fairly old (< R2014b) version of MATLAB, don't use datenums. Use datetimes:

>> datetime({'01-Jun-1980 00:00:00' '29-Aug-1980 09:36:00'})
ans = 
  1×2 datetime array
   01-Jun-1980 00:00:00   29-Aug-1980 09:36:00

[Dabbugottu Nagarjuna Rao]

Hello Sir, Thanks for your message and suggestion. I am using Matlab R2014a version. I need jjas each year (like 01-Jun-1980 00:00:00 01-Jul-1980 00:00:00 01-Aug-1980 00:00:00 thereafter for remaining years as before. I have resolved that issue using the below code. month=rem(time,12)+1; yr=1870+floor(time/12); for ii = 1:length(yr) dd{ii}=datenum(yr(ii),month(ii),1,0,0,0); disp(datestr(datenum(yr(ii),month(ii),1,0,0,0),0)); end