to change the format of date variable

[Olivia Johns]

hello,

I am trying to change the format of my date variable

currently, my date variable is arranged as


date
1947 - Q1
1947 - Q2
1947 - Q3
1947 - Q4
1948 - Q1


but I would like to change the format (I am just playing with it now), but when I use the command

format date %tq

it displays an error message,

"string %fmt required for string variables"


My date variable is a string variable. What can I do in this case?


Thanks a lot

[Nick Cox]

Changing the format won't change the contents of a variable.

For converting string date variables to numeric date variables, read

help datetime

In this example, consider

clear 
input str9 qdate 
"1947 - Q1"
"1947 - Q2"
"1947 - Q3"
"1947 - Q4"
"1948 - Q1"
end 

gen nqdate = quarterly(qdate, "YQ") 
format nqdate %tq 

list 

     +---------------------+
     |     qdate    nqdate |
     |---------------------|
  1. | 1947 - Q1    1947q1 |
  2. | 1947 - Q2    1947q2 |
  3. | 1947 - Q3    1947q3 |
  4. | 1947 - Q4    1947q4 |
  5. | 1948 - Q1    1948q1 |
     +---------------------+