|
Size: 1486
Comment:
|
Size: 2129
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 3: | Line 3: |
| Stata offers a set of macro features, each with slightly different behavior. | Stata supports a '''macro''' programming language. |
| Line 11: | Line 11: |
| == Globals == Global macros are declared with the `global` command. Generally these are discouraged, because their very nature (i.e. globally available) creates side-effects. {{{ global my-vars var1 var2 display "$my-vars appears as 'var1 var2'" display "${my-vars} appears the same" }}} == Locals == |
== Local Macros == |
| Line 28: | Line 16: |
| local my-vars var1 var2 display "`my-vars' appears as 'var1 var2'" |
local stringvars var1 var2 destring `stringvars', force |
| Line 31: | Line 20: |
To loop over words in a local macro, see [[Stata/Looping#Local_Macro_List|here]]. Note that looping creates local macros to store the current word. These local macros are accessed in the same manner {{{ foreach v of local stringvars { destring `v', force } }}} ---- |
|
| Line 34: | Line 35: |
| === Evaluation === | == Global Macros == Global macros are declared with the `global` command. Otherwise, the grammar and rules are exactly the same as local macros. {{{ global COHORT 1 }}} Generally these are discouraged, because their very nature (i.e. globally available) creates side-effects. To loop over words in a global macro, see [[Stata/Looping#Global_Macro_List|here]]. ---- == Expressions == |
| Line 44: | Line 62: |
| 100 vs. _N | 100 vs. 100 |
| Line 47: | Line 65: |
| ---- | |
| Line 48: | Line 67: |
| === Loops === | |
| Line 50: | Line 68: |
| Loops implicitly create local macros, which are accessed the same way. | == Functions == If a macro definition includes a colon (`:`), then what follows is a macro function. |
| Line 53: | Line 74: |
| foreach var of varlist var* { display "I found `var' while looping through all variables matching 'var*'" } foreach var of local my-vars { display "I found `var' while looping though `my-vars'" |
local cohorttype: type cohort if (strpos("`cohorttype'","str")>0) { destring cohort, replace |
| Line 62: | Line 80: |
| properties | |
| Line 63: | Line 82: |
| results | |
| Line 64: | Line 84: |
| == Scalars == | type |
| Line 66: | Line 86: |
| Scalars are ''essentially'' (and often ''used as'') a global macro. The distinguishing behavior is seen in arithmetic. | format |
| Line 68: | Line 88: |
| {{{ . local i=-2 . display `i'^2 -4 . display (`i')^2 4 . scalar j=-2 . display j^2 4 }}} |
value label |
| Line 79: | Line 90: |
| variable label | |
| Line 80: | Line 92: |
| data label sortedby label constraint char permname adosubdir dir sysdir environment e() r() s() all globals all scalars all matrices display list rownames colnames rowfullnames colfullnames roweq coleq rownumb colnumb roweqnumb coleqnumb rownfreeparms colnfreeparms rownlfs colnlfs rowsof colsof rowvarlist colvarlist rowlfnames collfnames tsnorm copy local copy global word piece strlen ustrlen udstrlen subinstr |
Macros
Stata supports a macro programming language.
Contents
Local Macros
Local macros are declared with the local command, and only exist in the local scope.
local stringvars var1 var2 destring `stringvars', force
To loop over words in a local macro, see here.
Note that looping creates local macros to store the current word. These local macros are accessed in the same manner
foreach v of local stringvars {
destring `v', force
}
Global Macros
Global macros are declared with the global command. Otherwise, the grammar and rules are exactly the same as local macros.
global COHORT 1
Generally these are discouraged, because their very nature (i.e. globally available) creates side-effects.
To loop over words in a global macro, see here.
Expressions
If a macro definition includes an equals sign (=), then what follows is evaluated as an expression.
. local count1 = _N . local count2 _N . display "`count1' vs. `count2'" 100 vs. _N . display "`count1' vs. " `count2' 100 vs. 100
Functions
If a macro definition includes a colon (:), then what follows is a macro function.
local cohorttype: type cohort
if (strpos("`cohorttype'","str")>0) {
destring cohort, replace
}properties
results
type
format
value label
variable label
data label
sortedby
label
constraint
char
permname
adosubdir
dir
sysdir
environment
e()
r()
s()
all globals
all scalars
all matrices
display
list
rownames
colnames
rowfullnames
colfullnames
roweq
coleq
rownumb
colnumb
roweqnumb
coleqnumb
rownfreeparms
colnfreeparms
rownlfs
colnlfs
rowsof
colsof
rowvarlist
colvarlist
rowlfnames
collfnames
tsnorm
copy local
copy global
word
piece
strlen
ustrlen
udstrlen
subinstr