How to find monthly average from daily data?

I have a file of 2000 row and 15 columns.First 3 coulmns contain year, month and day.It has 4 years of data of each day. other 12 cloumns contain my variables.This 12 columns has some missing data also.I want to find the monthly average of each variables of each year in one excel sheet.

Answer 1

[Star Strider]

You will need to combine the year, month, and day into one datetime array, and then replace the individual variables with the datetime array. (This should not be difficult with removevars and addvars.) Then use the table2timetable function to convert it to a timetable and then use the retime function.

[samira jahan]

What about the monthly average?

[Star Strider]

See the retime documentation section on Aggregate Timetable Data and Calculate Mean Values for an example. With your timetable, you would use 'monthly' instead of 'hourly' as in the documentation example. Other options are in the section on newTimeStep.