MATLAB: Finding rows which correspond to date

datetimefindtabletimetable

I have a table of data with two columns, one with monthly averaged data values and the other with the corresponding month and year in datetime 'MMM yyyy' format, e.g.
Jan 2004    26.3
Mar 2004    27.2
Jun 2004    35.5
Jan 2006    45.1
Mar 2007    32.2
How can I select each row beginning with a specific month eg. March (for each year), to then average these and get a representative average for that month over the full time span?
Many thanks!

Best Answer

>> Date = datetime({'Jan 2004';'Mar 2004';'Jun 2004';'Jan 2006';'Mar 2007'},'Format','MMM yyyy');
>> Value = [26.3;27.2;35.5;45.1;32.2];
>> t = table(Date,Value)
t =
  5×2 table
      Date      Value
    ________    _____
    Jan 2004    26.3 
    Mar 2004    27.2 
    Jun 2004    35.5 
    Jan 2006    45.1 
    Mar 2007    32.2 
>> t.Month = month(t.Date,'shortname')
t =
  5×3 table
      Date      Value    Month
    ________    _____    _____
    Jan 2004    26.3     'Jan'
    Mar 2004    27.2     'Mar'
    Jun 2004    35.5     'Jun'
    Jan 2006    45.1     'Jan'
    Mar 2007    32.2     'Mar'
>> monthly = varfun(@mean,t,'GroupingVariable','Month','InputVariable','Value')
monthly =
  3×3 table
    Month    GroupCount    mean_Value
    _____    __________    __________
    'Jan'        2            35.7   
    'Jun'        1            35.5   
    'Mar'        2            29.7
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