st: egen problem ? (was: poverty decomposition using povdeco command)

[adiallo5@worldbank.org]

Hi all,
Ousmane has recently raised a problem using povdeco.
In fact, his program crashes when egen is invoked.
In his code, all previous egen calculus went fine expect for a special
sum to be computed.
I was able to reproduce the problem using auto data.
However, I am not a so good programmer, so I seek the community's
help.
Suppose we have the fancy sum to compute. Here is the result.

. clear
. sysuse auto
(1978 Automobile Data)
. se tr on
.
.
. egen sume = sum(gear_ratio*displacement*length)/displ[1] , by(for)

-----------------------------------------------------------------------------------------
 begin egen ---
  - version 6
  - gettoken type 0 : 0, parse(" =(")
  - gettoken name 0 : 0, parse(" =(")
  - if`"`name'"'=="=" {
  = if`"="'=="=" {
  - local name `"`type'"'
  = local name `"sume"'
  - local type : set type
  - }
  - else {
    gettoken eqsign 0 : 0, parse(" =(")
    if `"`eqsign'"' != "=" {
    error 198
    }
    }
  - confirm new variable `name'
  = confirm new variable sume
  - gettoken fcn 0 : 0, parse(" =(")
  - gettoken args 0 : 0, parse(" ,") match(par)
  - if `"`par'"' != "(" {
  = if `"("' != "(" {
    exit 198
    }
  - if `"`args'"' == "_all" {
  = if `"gear_ratio*displacement*length"' == "_all" {
    version 7.0
    unab args : _all
    local args : subinstr local args "`_sortindex'" "", all word
    version 6.0
    }
  - syntax [if] [in] [, *]
varlist not allowed

-------------------------------------------------------------------------------------------
 end egen ---
r(101);


I do not why the last syntax is not going through.
And I do not have the programming
manual to find a solution.
Best regards.
Amadou Bassirou DIALLO.


PS: This calculus works fine.
. egen meany = sum(gear_rat*displ) , by(for)

-----------------------------------------------------------------------------------------
 begin egen ---
  - version 6
  - gettoken type 0 : 0, parse(" =(")
  - gettoken name 0 : 0, parse(" =(")
  - if`"`name'"'=="=" {
  = if`"="'=="=" {
  - local name `"`type'"'
  = local name `"meany"'
  - local type : set type
  - }
  - else {
    gettoken eqsign 0 : 0, parse(" =(")
    if `"`eqsign'"' != "=" {
    error 198
    }
    }
  - confirm new variable `name'
  = confirm new variable meany
  - gettoken fcn 0 : 0, parse(" =(")
  - gettoken args 0 : 0, parse(" ,") match(par)
  - if `"`par'"' != "(" {
  = if `"("' != "(" {
    exit 198
    }
  - if `"`args'"' == "_all" {
  = if `"gear_rat*displ"' == "_all" {
    version 7.0
    unab args : _all
    local args : subinstr local args "`_sortindex'" "", all word
    version 6.0
    }
  - syntax [if] [in] [, *]
  - if _by() {
    local byopt "by(`_byvars')"
    local cma ","
    }
  - else if `"`options'"' != "" {
  = else if `"by(for)"' != "" {
  - local cma ","
  - }
  - tempvar dummy
  - global EGEN_Varname `name'
  = global EGEN_Varname meany
  - capture noisily _g`fcn' `type' `dummy' = (`args') `if' `in' `cma' `byopt'
`options'
  = capture noisily _gsum float __000001 = (gear_rat*displ)   ,  by(for)

--------------------------------------------------------------------------------------
 begin _gsum ---
    - version 6
    - syntax newvarname =/exp [if] [in] [, BY(varlist)]
    - tempvar touse
    - quietly {
    - gen byte `touse'=1 `if' `in'
    = gen byte __000002=1
    - sort `touse' `by'
    = sort __000002 foreign
    - by `touse' `by': gen `typlist' `varlist' = sum(`exp') if `touse'==1
    = by __000002 foreign: gen float __000001 = sum((gear_rat*displ)   ) if
__000002==1
    - by `touse' `by': replace `varlist' = `varlist'[_N]
    = by __000002 foreign: replace __000001 = __000001[_N]
    - }

----------------------------------------------------------------------------------------
 end _gsum ---
  - global EGEN_Varname
  - if _rc { exit _rc }
  - quietly count if missing(`dummy')
  = quietly count if missing(__000001)
  - if r(N) {
    local s = cond(r(N)>1,"s","")
    di in bl "(" r(N) " missing value`s' generated)"
    }
  - rename `dummy' `name'
  = rename __000001 meany

-------------------------------------------------------------------------------------------
 end egen ---

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