how to convert date to numbers

so i have 200 dates on my data from 1st october....

i wanted to know if there was a trick to numbering the dates,

e.g. making 1st october=1

2nd october=2 etc

[Stephen23]

https://www.mathworks.com/help/matlab/ref/datetime.day.html

[Boss Man]

how would i convert my date in the excel file to numbers from matlab? i keep getting errors

[Ruger28]

What do your dates look like in MATLAB?

[Boss Man]

e.g.01-04-2019

however when i call them by xlsread im left with an empty matrix

[Boss Man]

fixed the date problem with readtable,it displays the date now

i now get this error when using day(t)

Undefined function 'day' for input arguments of type 'table'.

[dpb]

The variable t is your table; NOT the date variable inside the table. If it is named something original like 'Date', say, then

da=day(t.Date);

Answer 1

[Star Strider]

I showed you how to read them and do other operations on them in: How to combine date and time.

That also converts them to date numbers, and from there you can number them as you wish. The integer part of a date number are days, and the fractional parts are fractions of a day.

[Boss Man]

thanks :)

[Star Strider]

As always, my pleasure!