Gtools Macro Apr 2026

* Verify variable exists confirm variable `oldvar'

* Check if variable exists if "`replace'" == "" capture confirm new variable `newvar' if _rc != 0 di as error "Variable `newvar' already exists. Use replace option." exit 198

* Temporary variable for calculations tempvar tempvar * Apply if/in conditions marksample touse, novarlist mark `touse' `if' `in' * Create initial copy quietly gen `tempvar' = `oldvar' if `touse' gtools macro

*! gtools_macro.ado *! Full-featured data transformation and recoding tool *! Version 1.0

program define gtools_macro version 15 syntax [varlist] [if] [in] [, /// RECode(numlist) /// GENerate(string) /// LABel(string) /// CUTpoints(numlist) /// BINs(integer 5) /// STDize /// LOG /// SQRT /// SQUare /// RANK /// Center /// PErcentile(integer 10) /// TOPcode(real 99) /// BOTtomcode(real 1) /// MISSing(real .) /// REPLace /// DROPold /// VERBose /// SAVe(string) /// APPend(string) /// STATistics /// HELP /// ] * Verify variable exists confirm variable `oldvar' *

* Apply transformations in sequence local transform_count = 0 * 1. Topcode if "`topcode'" != "" quietly replace `tempvar' = `topcode' if `tempvar' > `topcode' & `tempvar' < . if "`verbose'" != "" di as text "Topcoded at: `topcode'" local transform_count = `transform_count' + 1 * 2. Bottomcode if "`bottomcode'" != "" quietly replace `tempvar' = `bottomcode' if `tempvar' < `bottomcode' & `tempvar' < . if "`verbose'" != "" di as text "Bottomcoded at: `bottomcode'" local transform_count = `transform_count' + 1 * 3. Missing values if "`missing'" != "" & `missing' != . quietly replace `tempvar' = . if `tempvar' == `missing' if "`verbose'" != "" di as text "Set value `missing' to missing" local transform_count = `transform_count' + 1 * 4. Recode if "`recode'" != "" local recode_list = "`recode'" * Parse recode rules (e.g., 1/5=1 6/10=2) local i = 1 while "`recode_list'" != "" gettoken rule recode_list: recode_list local equal_pos = strpos("`rule'", "=") if `equal_pos' > 0 local from = substr("`rule'", 1, `equal_pos'-1) local to = substr("`rule'", `equal_pos'+1, .) * Handle range (e.g., 1/5) local slash_pos = strpos("`from'", "/") if `slash_pos' > 0 local from_low = real(substr("`from'", 1, `slash_pos'-1)) local from_high = real(substr("`from'", `slash_pos'+1, .)) quietly replace `tempvar' = `to' if `tempvar' >= `from_low' & `tempvar' <= `from_high' & `tempvar' < . else quietly replace `tempvar' = `to' if `tempvar' == real("`from'") local i = `i' + 1 if "`verbose'" != "" di as text "Applied recoding" local transform_count = `transform_count' + 1 * 5. Cutpoints/Binning if "`cutpoints'" != "" local n_cuts: word count `cutpoints' local n_bins = `n_cuts' - 1 forvalues i = 1/`n_bins' local low: word `i' of `cutpoints' local high: word `=`i'+1' of `cutpoints' quietly replace `tempvar' = `i' if `tempvar' >= `low' & `tempvar' < `high' & `tempvar' < . if "`verbose'" != "" di as text "Binned using custom cutpoints" local transform_count = `transform_count' + 1 * 6. Equal-width bins if "`bins'" != "" & "`cutpoints'" == "" quietly summarize `tempvar' if `touse', meanonly local min = r(min) local max = r(max) local width = (`max' - `min') / `bins' forvalues i = 1/`bins' local low = `min' + (`i'-1)*`width' local high = `min' + `i'*`width' if `i' == `bins' quietly replace `tempvar' = `i' if `tempvar' >= `low' & `tempvar' <= `high' & `tempvar' < . else quietly replace `tempvar' = `i' if `tempvar' >= `low' & `tempvar' < `high' & `tempvar' < . if "`verbose'" != "" di as text "Created `bins' equal-width bins" local transform_count = `transform_count' + 1 * 7. Percentile groups if "`percentile'" != "" quietly egen `tempvar'_pct = pctile(`tempvar') if `touse', p(`percentile') quietly replace `tempvar' = `tempvar'_pct drop `tempvar'_pct if "`verbose'" != "" di as text "Created `percentile' percentile groups" local transform_count = `transform_count' + 1 * 8. Standardize if "`stdize'" != "" quietly summarize `tempvar' if `touse', meanonly local mean = r(mean) local sd = r(sd) quietly replace `tempvar' = (`tempvar' - `mean') / `sd' if "`verbose'" != "" di as text "Standardized (mean=`mean', sd=`sd')" local transform_count = `transform_count' + 1 * 9. Center if "`center'" != "" quietly summarize `tempvar' if `touse', meanonly local mean = r(mean) quietly replace `tempvar' = `tempvar' - `mean' if "`verbose'" != "" di as text "Centered (mean=`mean')" local transform_count = `transform_count' + 1 * 10. Log transformation if "`log'" != "" quietly replace `tempvar' = ln(`tempvar') if `tempvar' > 0 & `tempvar' < . if "`verbose'" != "" di as text "Applied natural log transformation" local transform_count = `transform_count' + 1 * 11. Square root if "`sqrt'" != "" quietly replace `tempvar' = sqrt(`tempvar') if `tempvar' >= 0 & `tempvar' < . if "`verbose'" != "" di as text "Applied square root transformation" local transform_count = `transform_count' + 1 * 12. Square if "`square'" != "" quietly replace `tempvar' = `tempvar'^2 if "`verbose'" != "" di as text "Applied square transformation" local transform_count = `transform_count' + 1 * 13. Rank if "`rank'" != "" quietly egen `tempvar'_rank = rank(`tempvar') if `touse' quietly replace `tempvar' = `tempvar'_rank drop `tempvar'_rank if "`verbose'" != "" di as text "Applied rank transformation" local transform_count = `transform_count' + 1 * Create final variable if "`replace'" != "" quietly replace `newvar' = `tempvar' if `touse' else quietly gen `newvar' = `tempvar' if `touse' * Apply variable label if "`label'" != "" label variable `newvar' "`label'" if "`verbose'" != "" di as text "Applied label: `label'" else if "`generate'" != "" label variable `newvar' "Transformed from `oldvar'" * Drop old variable if requested if "`dropold'" != "" & "`replace'" == "" drop `oldvar' if "`verbose'" != "" di as text "Dropped original variable: `oldvar'" * Display statistics if "`statistics'" != "" | "`verbose'" != "" di as text _n "Summary statistics for `newvar':" quietly summarize `newvar' if `touse', detail di as text " Observations: " as result r(N) di as text " Mean: " as result %9.4f r(mean) di as text " Std. Dev.: " as result %9.4f r(sd) di as text " Min: " as result %9.4f r(min) di as text " Max: " as result %9.4f r(max) di as text " Transformations applied: " as result `transform_count' * Save/Append results if "`save'" != "" preserve quietly tempfile results clear set obs 1 gen var = "`oldvar'" gen newvar = "`newvar'" gen N = r(N) gen mean = r(mean) gen sd = r(sd) gen min = r(min) gen max = r(max) gen transforms = `transform_count' gen date = date(c(current_date), "DMY") format date %td save "`save'", replace restore if "`verbose'" != "" di as text "Results saved to: `save'" if "`append'" != "" preserve quietly tempfile results clear set obs 1 gen var = "`oldvar'" gen newvar = "`newvar'" gen N = r(N) gen mean = r(mean) gen sd = r(sd) gen min = r(min) gen max = r(max) gen transforms = `transform_count' gen date = date(c(current_date), "DMY") format date %td save "`results'" use "`append'", clear append using "`results'" save "`append'", replace restore if "`verbose'" != "" di as text "Results appended to: `append'" if "`verbose'" != "" di as text _n "gtools_macro completed successfully" end

* Parse variable list - use first variable only tokenize `varlist' local oldvar = "`1'" Full-featured data transformation and recoding tool *

* Help display if "`help'" != "" di as text _n "gtools_macro - Comprehensive data transformation tool" di as text "==================================================" di as text "Options:" di as text " recode(numlist) - Recode values (e.g., 1/5=1 6/10=2)" di as text " generate(string) - Name of new variable" di as text " label(string) - Variable label for new variable" di as text " cutpoints(numlist)- Cut points for binning" di as text " bins(#) - Number of equal-width bins (default: 5)" di as text " stdize - Standardize to mean 0, sd 1" di as text " log - Natural log transformation" di as text " sqrt - Square root transformation" di as text " square - Square transformation" di as text " rank - Rank transformation" di as text " center - Center by subtracting mean" di as text " percentile(#) - Create percentile groups" di as text " topcode(#) - Topcode values above #" di as text " bottomcode(#) - Bottomcode values below #" di as text " missing(#) - Set specific value to missing" di as text " replace - Replace existing variable" di as text " dropold - Drop original variable" di as text " verbose - Display detailed output" di as text " save(filename) - Save results to file" di as text " append(filename) - Append results to file" di as text " statistics - Show summary statistics" exit

* Determine new variable name if "`generate'" == "" & "`replace'" == "" local newvar = "`oldvar'_transformed" else if "`generate'" != "" local newvar = "`generate'" else if "`replace'" != "" local newvar = "`oldvar'"

* Check if varlist provided if "`varlist'" == "" di as error "Error: varlist required" exit 198