How to write a for-loop that subsets my data based on different values of a string variable

[Noah Spencer]

I have what seems like a simple syntax issue that I can't figure out.

I want to write a for-loop that subsets my data based on different values of a string variable.

However, I keep getting a "type mismatch" error.

Here is an example of my problem:

sysuse auto, clear
foreach mk in "AMC Concord" {
    keep if make = "`mk'"
}

Any help would be much appreciated!

[Nick Cox]

In that case the problem appears to be needing == not =.

Supposing that your string variable has distinct values a b c d a problem is that you need to read in the dataset again.

Why not use if for analysis or frames?

foreach v in a b c d {
     use mydata, clear
     keep if myvar == "`x'"
     save mydata_`x'
}

[William Lisowski]

To compare two values, use "==" not "=" which is used to assign a value to a variable.

. sysuse auto, clear
(1978 automobile data)

. foreach mk in "AMC Concord" {
  2.     keep if make == "`mk'"
  3. }
(73 observations deleted)

.

[Noah Spencer]

Ah, that was a dumb mistake! Thanks Nick Cox and William Lisowski for pointing it out!