stata rencode源码

* rencode
* Program to encode variable and replace original as desired.
* Like encode, but can specify replace option instead of generate(name).
* This program also compresses the generated variable to a more efficient datatype if possible.
* Kenneth L. Simons, March 2006.
program define rencode
    version 9.0
    syntax varname [if] [in], [Generate(name) Label(name) NOExtend REPLACE]
    * Parse options.
    if "`replace'"=="" & "`generate'"=="" {
        di as error "Use the replace option to overwrite the original variable, or use the generate(name) option to create a new variable."
        error 197
    }
    if "`replace'"=="replace" & "`generate'"!="" {
        di as error "Specify only one of generate(name) or replace options.  Replace will overwrite the original variable."
        error 197
    }
    if "`replace'"=="replace" {
        tempvar toGenerate
        local generate `toGenerate'
        if "`label'"=="" {
            local label `varlist'
        }
        local varlabel: variable label `varlist'
    }
    if "`label'"=="" {
        local labelOption
    }
    else {
        local labelOption label(`label')
    }
    * Run the encode command.
    encode `varlist' `if' `in', generate(`generate') `labelOption' `noextend'
    quietly compress `generate'
    * If replacing the original variable, do so.
    if "`replace'"=="replace" {
        move `generate' `varlist'
        nobreak {
            drop `varlist'
            rename `generate' `varlist'
            label values `varlist' `label'
            if "`varlabel'"!="" {
                label variable `varlist' `"`varlabel'"'
            }
        }
    }
end