From discrete dates to continuous dates (revised)

I have a timetable T like

city date visitors
-----------------------
NY January 1 2020  100
NY January 5 2020   40
NY January 12 2020 300
SF January 1 2020  70
SF January 6 2020   240
SF January 15 2020 30

I want to embed this in a larger table with continuous dates such as

city date visitors
-----------------------
 NY January 1 2020  100
 NY January 2 2020  NaN
 NY January 3 2020  NaN
 NY January 4 2020  Nan
 NY January 5 2020   40
...

How can one do this?

[alpedhuez]

https://www.mathworks.com/matlabcentral/answers/167799-inserting-missing-dates-and-values

[the cyclist]

Can you upload the table you have in a MAT file, so that we don't have to guess at the date format?

Also, am I to understand that you do not want "2020" to appear in the added dates?

[alpedhuez]

Thank you. They are timetables. I have edited the question text.

Answer 1

[Steven Lord]

Here's a sample timetable.

dt = datetime(2020, 1, [1; 5; 12]);
T = timetable(dt, [100; 40; 300], 'VariableNames', "visitors");
T.Properties.DimensionNames{1} = 'date'

T = 3x1 timetable
       date        visitors
    ___________    ________

    01-Jan-2020      100   
    05-Jan-2020       40   
    12-Jan-2020      300   

retime it either filling rows not appearing in the original with missing (the default) or with the constant 0

T_fillWithMissing = retime(T, 'daily')

T_fillWithMissing = 12x1 timetable
       date        visitors
    ___________    ________

    01-Jan-2020      100   
    02-Jan-2020      NaN   
    03-Jan-2020      NaN   
    04-Jan-2020      NaN   
    05-Jan-2020       40   
    06-Jan-2020      NaN   
    07-Jan-2020      NaN   
    08-Jan-2020      NaN   
    09-Jan-2020      NaN   
    10-Jan-2020      NaN   
    11-Jan-2020      NaN   
    12-Jan-2020      300   

T_fillWith0 = retime(T, 'daily', 'fillwithconstant', 'Constant',0)

T_fillWith0 = 12x1 timetable
       date        visitors
    ___________    ________

    01-Jan-2020      100   
    02-Jan-2020        0   
    03-Jan-2020        0   
    04-Jan-2020        0   
    05-Jan-2020       40   
    06-Jan-2020        0   
    07-Jan-2020        0   
    08-Jan-2020        0   
    09-Jan-2020        0   
    10-Jan-2020        0   
    11-Jan-2020        0   
    12-Jan-2020      300   

[alpedhuez]

Thank you. I have edied the question that generalizes the previous question.