Experienced Stata users have often seen this advice: Do not loop over observations, as it is usually not the best way to do something. Here, however, is an example running contrary to that advice. The simple algorithm above is a good one; our only problem is translating it to Stata code...
With Stata 9, however, comes a more positive opportunity: to use Mata. The packageegenmoreon SSC includesegen, rowmedian(). It is much faster than previousegenfunctions—even though the basic loop is still a loop over observations—and it requires little extra memory. Here is the code: ...
局部宏 局部宏使用local语句,只在函数(program)、循环(loop)或者 .do文件里面使用: local myLocal price mpg length su `myLocal' 注意,全局宏的调用采用的是美元符号($),而局部宏的调用采用的是两个不同的撇符号(`')。 例1:创建一个名为levels的局部宏,它接受变量rep78中的每个唯一值,采用foreach循环遍历...
inf(`resid' ${countrylist}) vce(robust)estaddscalarnonzero=e(N)-e(N_zero)//Numberofnon-zeroobservationsestaddlocalcountryfe"Yes"estaddlocalte"Yes"}esttab,star(*0.10**0.05***0.01)keep(extractionrateres*)stats(NnonzeroN_zeropcountryfete,fmt(%9.0f%9.0f%9.0f%9.4fc%9.4fc))seb(4...
forvalues : loop over a numlist, performing a block of code local : define or modify a local macro (scalar variable) use : load a Stata data set save : write the contents of memory to a Stata data set insheet : load a text file in tab- or comma-delimited format ...
Delete observations: data new; set new; if var1 = 1 then delete; run; Drop observations: drop if var1 == 1 Loop over a variable list (varlist): data new(drop= i); set new; array raymond {4} var1 var2 var3 var4; do i = 1 to 4; if ...
2 The comma nd to extract all of the data is show n below.and forvalues loop the wavecomma nds.2HereListing the ?rst 20observations shows that we now have along panel dataset with two time periods.sort.listpid wav 33、e pid wavehid sexage mastatin 1/20,clea npidwavehidsexagemastat...
Existing command has new option that excludes observations with variables equal to system missing ( ) but not to extended missing ( , , , ); see [P] mark. This has to do with new emphasis on imputation of missing values; see [MI] intro. 7. New commands and make it easy to ...
foreachLoop over items forvaluesLoop over consecutive values frame postPost results to dataset in another frame fvexpandExpand factor varlists gettokenLow-level parsing H2O introIntroduction to integration with H2O ififprogramming command includeInclude commands from file ...
**Diverging Dot Plot sysuse auto, clear * Keeping first 20 observations as example keep in 1/20 * Standardizing variable egen double mpg_z = std(mpg) * Sorting the mpg_z and assigning rank sort mpg_z, stable generate rank_des = _n * Assigning label onto the sorted serial number lab...