STATA: Getting variable information into a local macro

All,

Many times one may want to get information from a variable and use it dynamically in your code. There is an easy and powerful way to do this.

Let's say that I wish to have a loop based on the max of a variable you can do

sum var1
local numbr : display r(max)
forvalues i = 1(1)`numbr' {
....
}

Anything that you can "display" you can get into a macro. To see a list of what you can recover type

return list

after you do the sum or sum, detail and

ereturn list

after a regression