Not that I have anything against -ds-, dear and sweet that it is, but
just to note that there are other ways to do this:
foreach var of var * {
capture confirm numeric variable `var'
if _rc {
replace `var' = "" if `var'_error == 1
}
else {
replace `var' = . if `var'_error == 1
}
}
Occasionally I have wanted a function say -sysmiss(<arg>)- that returns
string missing "" if <arg> is string and . otherwise. I am not sure if
it's really a good idea!
Nick
[email protected]
Nick Cox
To expand a little:
local num_vars r(varlist)
will just put the literal text "r(varlist)" in your macro. It won't put
the contents of r(varlist) in your macro.
Also
local num_vars r(varlist)
foreach var of local `num_vars' {
is equivalent to
foreach var of local r(varlist) {
which doesn't satisfy -foreach- because r(varlist) is not the name of a
local macro.
It is true that the error messages in each case are not illuminating!
Nick
[email protected]
Maarten buis
try:
foreach var of varlist `r(varlist)' {
That is: adding a "`" and a "'" around r(varlist)
Jennifer S. Earl
In the middle of a program I am working on, I need to set a bunch of
variables to missing, some of which are numeric and some of which are
string. Since the replace command is sensitive to numeric or string,
I need
to do separate foreach loops.
Here is what I have tried:
ds , has(type numeric)
local num_vars r(varlist)
foreach var of local num_vars {
replace `var'=. if `var'_error==1
}
ds , has(type string)
local string_vars r(varlist)
foreach var of local string_vars {
replace `var'="" if `var'_error==1
}
Unfortunately, when I try this, I get the following error:
time-series operators not allowed
r(101);
If I do instead (in case if is my foreach line that is giving me
problems):
ds , has(type numeric)
local num_vars r(varlist)
foreach var of local `num_vars' {
replace `var'=. if `var'_error==1
}
I get the following error:
{ required
r(100);
But, the puzzling part is that I see the right list of numeric
variables
displayed if I do:
ds , has(type numeric)
local num_vars r(varlist)
display `num_vars'
So, I know I am fetching the right list, I am just not able to
operate on
it in the foreach loop.
I have tried other ways of selecting off just the numeric variables
and
just the string and none are working.
Any suggestions? Maybe it is late and I missing something obvious?
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