Extracting last 4 digits of string

[katrina wilson]

I'm looking to extract the last four digits of a date formated as 07apr2021 to create a new variable, so right now i'm using

gen year=substr(fiscal_year_ended,-4,.)

which I think would work if I had only numerical/string values, but with a combination of both I'm for sure confusing the system. So I have since tried
gen year= (substr(string(fiscal_year_ended),-4,.)) but now I'm getting numbers that are not even prevalent in my data set. Advice?

[Nick Cox]

If your variable is a numeric daily date then it's an integer so substr() does not apply and even if you force the date to a string the last 4 characters are no use.

A numeric daily date usually has a display format as you cite but that doesn't make it a string.

Here's today's date. It is an integer on a scale on which 1 January 1960 was 0.

. di mdy(4, 7, 2021)
22377

That's convenient for calculations but useless for most human purposes, hence the ability to see a display format not just an integer: .

di %td mdy(4, 7, 2021)
07apr2021

If I want to see or get the year out of a daily date then there is a function for the purpose:

. di year(mdy(4, 7, 2021))
2021

Here di means display and is Stata's calculator command, among other things.

The last 4 characters of today's date are to Stata 2377 which is definitely not what you want.

At some point you'll need to look at help datetime !!!

[Nick Cox]

Cross-posted at https://www.reddit.com/r/stata/comme...from_a_string/

Katrina: Please see our cross-posting policy, which is explicit at https://www.statalist.org/forums/help#crossposting

I've often seen comments in forums that cross-posting in different forums without explaining the fact is rude and disrespectful, signalling that you don't care about duplicated effort. I wouldn't go that far, but as said the view exists.

Let's phrase this positively:

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2. If people want to know the answer too, they can look at the other site to see if an answer has been posted.

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Not explaining cross-posting implies that all relevant people are scanning all relevant forums, so that they don't need to be told about cross-posting. But that's empirically not correct. It's also inconsistent, as if all relevant people are scanning all relevant forums, you need only post in one of them.