How to convert a date into numerical for subtraction

[Saleh sharmah]

Dear members

I have the following date: 12-Dec-15 and would like to convert it to numerical so I can great a dummy variable equal to one if the data is less than 12-Dec-15 and zero otherwise.

What’s the right code to convert the data so I can use to create the dummy variable?

thanks for your help

[Nick Cox]

Consider

.

 di %td daily("12-Dec-15", "DMY", 2025)
12dec2015

. di %td daily("12-Dec-98", "DMY", 2025)
12dec1998

showing that you may need some variation on

gen wanted = daily(whatever, "DMY", 2025)

or

gen wanted = whatever < daily("12-Dec-15", "DMY", 2025)

except that

gen indicator = whatever < mdy(12, 12, 2015)

gets you there directly. All documented in

help datetime

[Nick Cox]

Same question at https://www.statalist.org/forums/for...or-subtraction

[Saleh sharmah]

Thank you so much, Nick for your help. Your second code worked well.