Subtract a part of a string depending on the number of digits

[Diego Malo]

Hello,

I have a string variable, let's called it "string". Sometimes it has 10 digits, and some times 9. I would like to obtain create a new variable which takes the first 8 digit if it has 10 digits, and to takes the first 7 digit if it has 9 digit.

I know how to do it considering just one part:

gen wanted = substr(string, 1, 8)

However, I have not found the way of doing both parts at the same time. Any ideas?

[daniel klein]

gen wanted = string(trunc(real(string)/100), "%18.0g")

[Andrew Musau]

See

help length()

and

help cond()

If it is a binary condition, i.e., either a value is 10 digits long or 9 digits long, then you can have

gen wanted= cond(length(stringvar)==10, substr(stringvar, 1, 8), substr(stringvar, 1, 7))

If there are more possibilities, specify multiple conditions.

Note: Crossed with #2.

[Diego Malo]

Andrew Musau Thanks a lot Andrew! It works perfectly. I did not know the existence of length() command.

daniel klein Thanks a lot for your answer! I also tried your solution and it also works! However for some numbers it gives me the result in scientific notation.

[daniel klein]

daniel klein Thanks a lot for your answer! I also tried your solution and it also works! However for some numbers it gives me the result in scientific notation.

That should have been fixed with the edited post, including the "%18.0g" display format.